Adding upstream version 86.0.1.upstream/86.0.1 upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
author: Daniel Baumann <daniel.baumann@progress-linux.org> 2024-04-28 14:29:10 +0000
committer: Daniel Baumann <daniel.baumann@progress-linux.org> 2024-04-28 14:29:10 +0000
commit: 2aa4a82499d4becd2284cdb482213d541b8804dd (patch)
tree: b80bf8bf13c3766139fbacc530efd0dd9d54394c /l10n-cy/toolkit
parent: Initial commit. (diff)
download: firefox-2aa4a82499d4becd2284cdb482213d541b8804dd.tar.xz
firefox-2aa4a82499d4becd2284cdb482213d541b8804dd.zip
106 files changed, 5614 insertions, 0 deletions
diff --git a/l10n-cy/toolkit/chrome/alerts/alert.dtd b/l10n-cy/toolkit/chrome/alerts/alert.dtd
new file mode 100644
index 0000000000..da0e9dd2d8
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/alerts/alert.dtd
@@ -0,0 +1,6 @@
+<!-- This Source Code Form is subject to the terms of the Mozilla Public
+   - License, v. 2.0. If a copy of the MPL was not distributed with this
+   - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
+
+<!ENTITY     closeAlert.tooltip          "Cau'r hysbysiad">
+<!ENTITY     settings.label              "Gosodiadau">
diff --git a/l10n-cy/toolkit/chrome/alerts/alert.properties b/l10n-cy/toolkit/chrome/alerts/alert.properties
new file mode 100644
index 0000000000..c1715f4ee6
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/alerts/alert.properties
@@ -0,0 +1,23 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# LOCALIZATION NOTE(closeButton.title): Used as the close button text for web notifications on OS X.
+# This should ideally match the string that OS X uses for the close button on alert-type
+# notifications. OS X will truncate the value if it's too long.
+closeButton.title = Cau
+# LOCALIZATION NOTE(actionButton.label): Used as the button label to provide more actions on OS X notifications. OS X will truncate this if it's too long.
+actionButton.label = …
+# LOCALIZATION NOTE(webActions.disableForOrigin.label): %S is replaced
+# with the hostname origin of the notification.
+webActions.disableForOrigin.label = Analluogi hysbysiadau o %S
+
+# LOCALIZATION NOTE(source.label): Used to show the URL of the site that
+# sent the notification (e.g., "via mozilla.org"). "%1$S" is the source host
+# and port.
+source.label=drwy %1$S
+webActions.settings.label = Gosodiadau hysbysiadau
+
+# LOCALIZATION NOTE(pauseNotifications.label): %S is replaced with the
+# brandShortName of the application.
+pauseNotifications.label = Oedi hysbysiadau nes i %S ailgychwyn
diff --git a/l10n-cy/toolkit/chrome/autoconfig/autoconfig.properties b/l10n-cy/toolkit/chrome/autoconfig/autoconfig.properties
new file mode 100644
index 0000000000..664315eab2
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/autoconfig/autoconfig.properties
@@ -0,0 +1,12 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+readConfigTitle = Gwall Ffurfweddiad
+readConfigMsg = Methwyd darllen y ffeil ffurfweddiad. Cysylltwch â'ch gweinyddwr system.
+
+autoConfigTitle = Rhybudd AutoConfig
+autoConfigMsg = Methodd Netscape.cfg/AutoConfig. Cysylltwch â'ch gweinyddwr system.\n Gwall: methodd %S:
+
+emailPromptTitle = Cyfeiriad E-bost
+emailPromptMsg = Rhowch eich cyfeiriad e-bost
diff --git a/l10n-cy/toolkit/chrome/global-platform/mac/intl.properties b/l10n-cy/toolkit/chrome/global-platform/mac/intl.properties
new file mode 100644
index 0000000000..71265a9ef1
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global-platform/mac/intl.properties
@@ -0,0 +1,7 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# LOCALIZATION NOTE (intl.ellipsis): Use the unicode ellipsis char, \u2026,
+# or use "..." if \u2026 doesn't suit traditions in your locale.
+intl.ellipsis=…
diff --git a/l10n-cy/toolkit/chrome/global-platform/mac/platformKeys.properties b/l10n-cy/toolkit/chrome/global-platform/mac/platformKeys.properties
new file mode 100644
index 0000000000..e1ce2fd906
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global-platform/mac/platformKeys.properties
@@ -0,0 +1,34 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+#mac
+#this file defines the on screen display names for the various modifier keys
+#these are used in XP menus to show keyboard shortcuts
+
+# Platform: Mac
+# This file defines the on-screen display names for the various modifier keys
+# and the Return key (VK_RETURN).
+# These are used in XP menus to show keyboard shortcuts.
+
+# The Shift key - open up arrow symbol (ctrl-e)
+VK_SHIFT=⇧
+
+# The Command key - clover leaf symbol (ctrl-q)
+VK_META=⌘
+
+# The Win key - never generated by native key event
+VK_WIN=win
+
+# The Option/Alt key - splitting tracks symbol (ctrl-g)
+VK_ALT=⌥
+
+# The Control key - hat symbol (ctrl-f)
+VK_CONTROL=⌃
+
+# The Return key (on the main keyboard or numpad):
+# "Enter" on Windows/Unix, "Return" on Mac
+VK_RETURN=Return
+
+# The separator character used between modifiers (none on Mac OS)
+MODIFIER_SEPARATOR=
diff --git a/l10n-cy/toolkit/chrome/global-platform/unix/intl.properties b/l10n-cy/toolkit/chrome/global-platform/unix/intl.properties
new file mode 100644
index 0000000000..71265a9ef1
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global-platform/unix/intl.properties
@@ -0,0 +1,7 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# LOCALIZATION NOTE (intl.ellipsis): Use the unicode ellipsis char, \u2026,
+# or use "..." if \u2026 doesn't suit traditions in your locale.
+intl.ellipsis=…
diff --git a/l10n-cy/toolkit/chrome/global-platform/unix/platformKeys.properties b/l10n-cy/toolkit/chrome/global-platform/unix/platformKeys.properties
new file mode 100644
index 0000000000..28e77ecaa5
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global-platform/unix/platformKeys.properties
@@ -0,0 +1,34 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+#default
+#this file defines the on screen display names for the various modifier keys
+#these are used in XP menus to show keyboard shortcuts
+
+# Platform: Unix
+# This file defines the on-screen display names for the various modifier keys
+# and the Enter key (VK_RETURN).
+# These are used in XP menus to show keyboard shortcuts.
+
+# The Shift key
+VK_SHIFT=Shift
+
+# The Command key
+VK_META=Meta
+
+# The Win key (Super key and Hyper keys are mapped to DOM Win key)
+VK_WIN=Win
+
+# The Alt key
+VK_ALT=Alt
+
+# The Control key
+VK_CONTROL=Ctrl
+
+# The Enter key (on the main keyboard or numpad):
+# "Enter" on Windows/Unix, "Return" on Mac
+VK_RETURN=Enter
+
+# The separator character used between modifiers
+MODIFIER_SEPARATOR=+
diff --git a/l10n-cy/toolkit/chrome/global-platform/win/intl.properties b/l10n-cy/toolkit/chrome/global-platform/win/intl.properties
new file mode 100644
index 0000000000..71265a9ef1
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global-platform/win/intl.properties
@@ -0,0 +1,7 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# LOCALIZATION NOTE (intl.ellipsis): Use the unicode ellipsis char, \u2026,
+# or use "..." if \u2026 doesn't suit traditions in your locale.
+intl.ellipsis=…
diff --git a/l10n-cy/toolkit/chrome/global-platform/win/platformKeys.properties b/l10n-cy/toolkit/chrome/global-platform/win/platformKeys.properties
new file mode 100644
index 0000000000..2d0dd84b95
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global-platform/win/platformKeys.properties
@@ -0,0 +1,34 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+#default
+#this file defines the on screen display names for the various modifier keys
+#these are used in XP menus to show keyboard shortcuts
+
+# Platform: Windows
+# This file defines the on-screen display names for the various modifier keys
+# and the Enter key (VK_RETURN).
+# These are used in XP menus to show keyboard shortcuts.
+
+# The Shift key
+VK_SHIFT=Shift
+
+# The Command key
+VK_META=Meta
+
+# The Win key
+VK_WIN=Win
+
+# The Alt key
+VK_ALT=Alt
+
+# The Control key
+VK_CONTROL=Ctrl
+
+# The Enter key (on the main keyboard or numpad):
+# "Enter" on Windows/Unix, "Return" on Mac
+VK_RETURN=Enter
+
+# The separator character used between modifiers
+MODIFIER_SEPARATOR=+
diff --git a/l10n-cy/toolkit/chrome/global/aboutReader.properties b/l10n-cy/toolkit/chrome/global/aboutReader.properties
new file mode 100644
index 0000000000..9d2a7d9dc0
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/aboutReader.properties
@@ -0,0 +1,66 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+#LOCALIZATION NOTE (aboutReader.loading2):
+# Use the unicode ellipsis char, \u2026,
+# or use "..." if \u2026 doesn't suit traditions in your locale.
+aboutReader.loading2=Llwytho…
+aboutReader.loadError=Methwyd llwytho erthygl o dudalen
+
+aboutReader.colorScheme.light=Golau
+aboutReader.colorScheme.dark=Tywyll
+aboutReader.colorScheme.sepia=Sepia
+aboutReader.colorScheme.auto=Awtomatig
+
+# LOCALIZATION NOTE (aboutReader.estimatedReadTimeValue1): Semi-colon list of plural forms.
+# See: http://developer.mozilla.org/en/docs/Localization_and_Plurals
+# #1 is the number of minutes it is estimated to take to read the article
+# example: `3 minutes`
+aboutReader.estimatedReadTimeValue1=Dim munudau;#1 munud;#1 funud;#1 munud;#1 munud;#1 munud
+
+#LOCALIZATION NOTE (aboutReader.estimatedReadTimeRange1): Semi-colon list of plural forms.
+# See: http://developer.mozilla.org/en/docs/Localization_and_Plurals
+# When there is some uncertainty in how long the article will take to read show a range of
+# minutes it is expected to take.
+# #1 is the number of minutes it is estimated to take to read the article for a fast reader
+# #2 is the number of minutes it is estimated to take to read the article for a slow reader
+# #2 is the variable used to determine the plural form to use.
+# example: `5-8 minutes`
+aboutReader.estimatedReadTimeRange1=Dim munudau;#1-#2 munud;#1-#2 munud;#1-#2 munud;#1-#2 munud;#1-#2 munud
+
+# LOCALIZATION NOTE (aboutReader.fontType.serif, aboutReader.fontType.sans-serif):
+# These are the styles of typeface that are options in the reader view controls.
+aboutReader.fontType.serif=Serif
+aboutReader.fontType.sans-serif=Sans-serif
+
+# LOCALIZATION NOTE (aboutReader.fontTypeSample): String used to sample font types.
+# For followup see: https://bugzilla.mozilla.org/show_bug.cgi?id=1637089 
+aboutReader.fontTypeSample=Aa
+
+aboutReader.toolbar.close=Cau'r Golwg Darllen
+aboutReader.toolbar.typeControls=Rheoli'r math
+
+# This is used as a label for the Reader View toolbar button.
+# This is a label used for the Save to Pocket option in the toolbar.
+# %S is replaced by Pocket.
+readerView.savetopocket.label=Cadw i %S
+# This is a label used for done option in the toolbar
+readerView.done.label=Gorffen
+# These are used for the Reader View toolbar button and the menuitem within the
+# View menu.
+readerView.enter=Mynd i'r Golwg Darllen
+readerView.enter.accesskey=D
+readerView.close=Cau'r Golwg Darllen
+readerView.close.accesskey=D
+
+# These are used as tooltips in Type Control
+aboutReader.toolbar.minus = Lleihau Maint Testun
+aboutReader.toolbar.plus = Cynyddu Maint Testun
+aboutReader.toolbar.contentwidthminus = Lleihau Lled Cynnwys
+aboutReader.toolbar.contentwidthplus = Cynyddu Lled Cynnwys
+aboutReader.toolbar.lineheightminus = Lleihau Uchder Llinell
+aboutReader.toolbar.lineheightplus = Cynyddu Uchder Llinell
+aboutReader.toolbar.colorschemelight = Cynllun Lliw Golau
+aboutReader.toolbar.colorschemedark = Cynllun Lliw Tywyll
+aboutReader.toolbar.colorschemesepia = Cynllun Lliw Sepia
diff --git a/l10n-cy/toolkit/chrome/global/aboutStudies.properties b/l10n-cy/toolkit/chrome/global/aboutStudies.properties
new file mode 100644
index 0000000000..657c144b3f
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/aboutStudies.properties
@@ -0,0 +1,33 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+# LOCALIZATION NOTE (title): keep "Shield" in English. See
+# https://wiki.mozilla.org/Firefox/Shield/Shield_Studies for more information
+title = Shield Studies
+removeButton = Tynnu
+
+# LOCALIZATION NOTE (activeStudiesList): Title above a list of active studies
+activeStudiesList = Astudiaethau byw
+# LOCALIZATION NOTE (activeStudiesList): Title above a list of completed studies
+completedStudiesList = Astudiaethau wedi'u cwblhau
+# LOCALIZATION NOTE (activeStatus): Displayed for an active study
+activeStatus = Gweithredol
+
+# LOCALIZATION NOTE (completeStatus): Displayed for a study that is already complete
+completeStatus = Cwblhawyd
+
+updateButtonWin = Ddiweddaru Dewisiadau
+updateButtonUnix = Diweddaru Dewisiadau
+learnMore = Dysgu rhagor
+noStudies = Nid ydych wedi cymryd rhan mewn unrhyw astudiaeth.
+disabledList = Dyma restr o astudiaethau rydych wedi cymryd rhan ynddynt. Ni fydd unrhyw astudiaethau newydd yn rhedeg.
+# LOCALIZATION NOTE (enabledList): %S is brandShortName (e.g. Firefox)
+enabledList = Beth yw hyn? Gall %S osod a rhedeg astudiaethau o bryd i'w gilydd.
+
+# LOCALIZATION NOTE (preferenceStudyDescription) $1%S will be replaced with the
+# name of a preference (such as "stream.improvesearch.topSiteSearchShortcuts")
+# and $2%S will be replaced with the value of that preference. Both values will
+# be formatted differently than the surrounding text.
+preferenceStudyDescription = Mae'r astudiaeth yn gosod %1$S i %2$S.
+\ No newline at end of file
diff --git a/l10n-cy/toolkit/chrome/global/aboutWebrtc.properties b/l10n-cy/toolkit/chrome/global/aboutWebrtc.properties
new file mode 100644
index 0000000000..eddae0c219
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/aboutWebrtc.properties
@@ -0,0 +1,191 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# LOCALIZATION NOTE (document_title):
+# The text "WebRTC" is a proper noun and should not be translated.
+# It is the general label for the standards based technology. see http://www.webrtc.org
+document_title = Materion Mewnol WebRTC
+cannot_retrieve_log = Methu estyn cofnod data WebRTC
+
+# LOCALIZATION NOTE (save_page_msg):
+# %1$S will be replaced by a full path file name: the target of the SavePage operation.
+save_page_msg = cadwyd y dudalen i: %1$S
+
+# LOCALIZATION NOTE (save_page_dialog_title): "about:webrtc" is a internal browser URL and should not be
+# translated. This string is used as a title for a file save dialog box.
+save_page_dialog_title = cadw about:webrtc fel
+
+# LOCALIZATION NOTE (debug_mode_off_state_msg):
+# %1$S will be replaced by the full path file name of the debug log.
+debug_mode_off_state_msg = mae modd canfod y cofnod olrhain yn: %1$S
+
+# LOCALIZATION NOTE (debug_mode_on_state_msg):
+# %1$S will be replaced by the full path file name of the debug log.
+debug_mode_on_state_msg = modd dadfygio'n weithredol, cofnod olrhain yn %1$S
+
+# LOCALIZATION NOTE (aec_logging_msg_label, aec_logging_off_state_label,
+# aec_logging_on_state_label, aec_logging_on_state_msg):
+# AEC is an abbreviation for Acoustic Echo Cancellation.
+aec_logging_msg_label = Cofnodi AEC
+aec_logging_off_state_label = Cychwyn Cofnodi AEC
+aec_logging_on_state_label = Atal Cofnodi AEC
+aec_logging_on_state_msg = Cofnodi AEC yn weithredol (siarad gyda'r galwr am ychydig funudau ac yna atal y cipio)
+
+# LOCALIZATION NOTE (aec_logging_off_state_msg):
+# %1$S will be replaced by the full path to the directory containing the captured log files.
+# AEC is an abbreviation for Acoustic Echo Cancellation.
+aec_logging_off_state_msg = mae'r ffeiliau cofnod y cipio yn: %1$S
+
+# LOCALIZATION NOTE (peer_connection_id_label): "PeerConnection" is a proper noun
+# associated with the WebRTC module. "ID" is an abbreviation for Identifier. This string
+# should not normally be translated and is used as a data label.
+peer_connection_id_label = Dynodiad PeerConnection
+
+# LOCALIZATION NOTE (sdp_heading, local_sdp_heading, remote_sdp_heading, sdp_history_heading, sdp_parsing_errors_heading):
+# "SDP" is an abbreviation for Session Description Protocol, an IETF standard.
+# See http://wikipedia.org/wiki/Session_Description_Protocol
+sdp_heading = SDP
+local_sdp_heading = SDP lleol
+remote_sdp_heading = SDP pell
+
+sdp_history_heading = Hanes SDP
+sdp_parsing_errors_heading = Gwallau Didoli SDP
+# LOCALIZATION NOTE (sdp_set_at_timestamp): the local or remote SDP and when it was set
+# %1$S will be replaced by local_sdp_heading or remote sdp_heading and %2$S
+# will be a numeric timestamp.
+sdp_set_at_timestamp = Gosod %1$S ar y stamp amser %2$S.
+# LOCALIZATION NOTE (sdp_set_timestamp): the absolute and relative times
+# when the sdp was set. %1$S and $2$S are both numeric timestamps. The
+# first is the absolute time, the second is the elapsed time since the
+# first sdp was set. ms is an abbreviation for milliseconds.
+sdp_set_timestamp = Stamp amser %1$S (+ %2$S ms)
+# LOCALIZATION NOTE (offer, answer):
+# offer and answer describe whether the local sdp is an offer or answer or
+# the remote sdp is an offer or answer.  These are appended to the local and
+# remote sdp headings.
+offer = Cynnig
+answer = Ateb
+
+# LOCALIZATION NOTE (rtp_stats_heading): "RTP" is an abbreviation for the
+# Real-time Transport Protocol, an IETF specification, and should not
+# normally be translated. "Stats" is an abbreviation for Statistics.
+rtp_stats_heading = Ystadegau RTP
+
+# LOCALIZATION NOTE (ice_state, ice_stats_heading): "ICE" is an abbreviation
+# for Interactive Connectivity Establishment, which is an IETF protocol,
+# and should not normally be translated. "Stats" is an abbreviation for
+# Statistics.
+ice_state = Cyflwr ICE
+ice_stats_heading = Ystadegau ICE
+ice_restart_count_label = Ailgychwyn ICE
+ice_rollback_count_label = Hen fersiynau ICE
+ice_pair_bytes_sent = Didau wedi'u hanfon
+ice_pair_bytes_received = Didau wedi'u derbyn
+ice_component_id = Enw'r Cydran
+
+# LOCALIZATION NOTE (avg_bitrate_label, avg_framerate_label): "Avg." is an abbreviation
+# for Average. These are used as data labels.
+avg_bitrate_label = Did radd cyfartalog
+avg_framerate_label = Ffrâm radd cyfartalog
+
+# LOCALIZATION NOTE (typeLocal, typeRemote): These adjectives are used to label a
+# line of statistics collected for a peer connection. The data represents
+# either the local or remote end of the connection.
+typeLocal = Lleol
+typeRemote = Pell
+
+# LOCALIZATION NOTE (nominated): This adjective is used to label a table column.
+# Cells in this column contain the localized javascript string representation of "true"
+# or are left blank.
+nominated = Enwebwyd
+
+# LOCALIZATION NOTE (selected): This adjective is used to label a table column.
+# Cells in this column contain the localized javascript string representation of "true"
+# or are left blank. This represents an attribute of an ICE candidate.
+selected = Dewiswyd
+
+# LOCALIZATION NOTE (trickle_caption_msg2, trickle_highlight_color_name2): ICE
+# candidates arriving after the remote answer arrives are considered trickled
+# (an attribute of an ICE candidate). These are highlighted in the ICE stats
+# table with light blue background. %S is replaced by
+# trickle_highlight_color_name2 ("blue"), highlighted with a light blue
+# background to visually match the trickled ICE candidates.
+trickle_caption_msg2 = Mae ymgeisydd diferu (yn cyrraedd ar ôl yr ateb) yn cael eu hamlygu mewn %S
+trickle_highlight_color_name2 = glas
+
+save_page_label = Cadw Tudalen
+debug_mode_msg_label = Modd Dadfygio
+debug_mode_off_state_label = Cychwyn y Modd Dadfygio
+debug_mode_on_state_label = Atal y Modd Dadfygio
+stats_heading = Ystadegau'r Sesiwn
+stats_clear = Clirio Hanes
+log_heading = Cofnod Cysylltu
+log_clear = Clirio'r Cofnod
+log_show_msg = dangos cofnod
+log_hide_msg = cuddio cofnod
+connection_closed = cau
+local_candidate = Ymgeisydd Lleol
+remote_candidate = Ymgeisydd Pell
+raw_candidates_heading = Pob Ymgeisydd Bras
+raw_local_candidate = Ymgeisydd Lleol Bras
+raw_remote_candidate = Ymgeisydd Pell Bras
+raw_cand_show_msg = dangos ymgeiswyr bras
+raw_cand_hide_msg = cuddio ymgeiswyr bras
+priority = Blaenoriaeth
+fold_show_msg = dangos manylion
+fold_show_hint = cliciwch i ehangu'r adran
+fold_hide_msg = cuddio manylion
+fold_hide_hint = cliciwch i gau'r adran
+dropped_frames_label = Fframiau hepgorwyd
+discarded_packets_label = Pacedi hepgorwyd
+decoder_label = Datgodwyr
+encoder_label = Amgodiwr
+received_label = Derbyniwyd
+packets = pacedi
+lost_label = Wedi'i golli
+jitter_label = Jitter
+sent_label = Anfonwyd
+
+show_tab_label = Dangos tab
+
+frame_stats_heading = Ystadegau Ffrâm Fideo
+n_a = Dim Ar Gael
+width_px = Lled (px)
+height_px = Uchder (px)
+consecutive_frames = Fframiau Olynol
+time_elapsed = Amser wedi Pasio
+estimated_framerate = Amcan o Raddfa Ffrâm
+rotation_degrees = Cylchdroi (graddau)
+first_frame_timestamp = Stamp Amser Derbyn y  Ffrâm Gyntaf
+last_frame_timestamp = Stamp Amser Derbyn y  Ffrâm Olaf
+# SSRCs are identifiers that represent endpoints in an RTP stream
+# This is an SSRC on the local side of the connection that is receiving RTP
+local_receive_ssrc = Derbyn SSRC  Lleol
+# This is an SSRC on the remote side of the connection that is sending RTP
+remote_send_ssrc = Anfon SSRC o Bell
+# An option whose value will not be displayed but instead noted as having been
+# provided
+configuration_element_provided = Wedi'i Ddarparu
+# An option whose value will not be displayed but instead noted as having not
+# been provided
+configuration_element_not_provided = Heb ei Ddarparu
+# The options set by the user in about:config that could impact a WebRTC call
+custom_webrtc_configuration_heading = Dewisiadau WebRTC Gosodedig y Defnyddiwr
+
+# Section header for estimated bandwidths of WebRTC media flows
+bandwidth_stats_heading = Amcangyfrif Lled Band
+# The ID of the MediaStreamTrack
+track_identifier = Dynodwr tracio
+# The estimated bandwidth available for sending WebRTC media in bytes per second
+send_bandwidth_bytes_sec = Lled Band Anfon (beit/eiliad)
+# The estimated bandwidth available for receiving WebRTC media in bytes per second
+receive_bandwidth_bytes_sec = Lled Band Derbyn (beit/eiliad)
+# Maximum number of bytes per second that will be padding zeros at the ends of packets
+max_padding_bytes_sec = Uchafswm Padio (beit/eiliad)
+# The amount of time inserted between packets to keep them spaced out
+pacer_delay_ms = Oedi Pacer ms
+# The amount of time it takes for a packet to travel from the local machine to the remote machine,
+# and then have a packet return
+round_trip_time_ms = RTT ms
+
diff --git a/l10n-cy/toolkit/chrome/global/appPicker.dtd b/l10n-cy/toolkit/chrome/global/appPicker.dtd
new file mode 100644
index 0000000000..f2ae20d749
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/appPicker.dtd
@@ -0,0 +1,7 @@
+<!-- This Source Code Form is subject to the terms of the Mozilla Public
+   - License, v. 2.0. If a copy of the MPL was not distributed with this
+   - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
+
+<!ENTITY NoAppFound.label      "Heb ganfod rhaglen ar gyfer y math yma o ffeil.">
+<!ENTITY BrowseButton.label    "Pori…">
+<!ENTITY SendMsg.label         "Anfon yr eitem at:">
diff --git a/l10n-cy/toolkit/chrome/global/autocomplete.properties b/l10n-cy/toolkit/chrome/global/autocomplete.properties
new file mode 100644
index 0000000000..a311f5b31b
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/autocomplete.properties
@@ -0,0 +1,29 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# LOCALIZATION NOTE (searchWithEngine, searchInPrivateWindowWithEngine): %S will
+# be replaced with the search engine provider's name. This format was chosen
+# because the provider can also end with "Search" (e.g.: MSN Search).
+searchWithEngine = Chwilio gyda %S
+
+searchInPrivateWindowWithEngine = Chwilio gyda %S mewn Ffenestr Breifat
+
+# LOCALIZATION NOTE (searchInPrivateWindow): Used when the private browsing
+# engine is the same as the default engine.
+searchInPrivateWindow = Chwilio mewn Ffenestr Breifat
+
+# LOCALIZATION NOTE (switchToTab2): This is the same as the older switchToTab
+# string that it's replacing, except it uses title case, so "Switch" and "Tab"
+# are capitalized.
+switchToTab2 = Newid i'r Tab
+
+# LOCALIZATION NOTE (visit): This is shown next to autocomplete entries that are
+# simple URLs or sites, which will be visited when the user selects them.
+visit = Ymweld â
+
+# LOCALIZATION NOTE (bookmarkKeywordSearch): This is the title of autocomplete
+# entries that are bookmark keyword searches.  %1$S will be replaced with the
+# domain name of the bookmark, and %2$S will be replaced with the keyword
+# search text that the user is typing.  %2$S will not be empty.
+bookmarkKeywordSearch = %1$S: %2$S
diff --git a/l10n-cy/toolkit/chrome/global/browser.properties b/l10n-cy/toolkit/chrome/global/browser.properties
new file mode 100644
index 0000000000..74cc051c90
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/browser.properties
@@ -0,0 +1,7 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+formPostSecureToInsecureWarning.title = Rhybudd Diogelwch
+formPostSecureToInsecureWarning.message = Mae'r wybodaeth rydych wedi ei gyflwyno ar fin cael ei yrru ar draws cysylltiad sydd heb ei hamgryptio a gall gael ei ddarllen gan drydydd parti.\n\nYdych chi'n siŵr eich bod eisiau parhau i yrru'r wybodaeth?
+formPostSecureToInsecureWarning.continue = Ymlaen
diff --git a/l10n-cy/toolkit/chrome/global/charsetMenu.dtd b/l10n-cy/toolkit/chrome/global/charsetMenu.dtd
new file mode 100644
index 0000000000..b917d036b3
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/charsetMenu.dtd
@@ -0,0 +1,5 @@
+<!-- This Source Code Form is subject to the terms of the Mozilla Public
+   - License, v. 2.0. If a copy of the MPL was not distributed with this
+   - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
+
+<!ENTITY charsetMenu2.label            "Amgodiad Testun">
diff --git a/l10n-cy/toolkit/chrome/global/charsetMenu.properties b/l10n-cy/toolkit/chrome/global/charsetMenu.properties
new file mode 100644
index 0000000000..105a666568
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/charsetMenu.properties
@@ -0,0 +1,127 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# LOCALIZATION NOTE: The property keys ending with ".key" are for access keys.
+# Localizations may add or delete properties where the property key ends with
+# ".key" as appropriate for the localization. The code that uses this data can
+# deal with the absence of an access key for an item.
+#
+# For gbk, gbk.bis and gbk.bis.key are used to trigger string changes in
+# localizations.
+#
+# In the en-US version of this file, access keys are given to the following:
+# * UTF-8
+# * All encodings that are the fallback encoding for some locale in Firefox
+# * All encodings that are the fallback encoding for some locale in IE
+# * All Japanese encodings
+#
+# For the items whose property key does not end in ".key" and whose value
+# includes "(" U+0028 LEFT PARENTHESIS, the "(" character is significant for
+# processing by CharsetMenu.jsm. If your localization does not use ASCII
+# parentheses where en-US does in this file, please file a bug to make
+# CharsetMenu.jsm also recognize the delimiter your localization uses.
+# (When this code was developed, all localizations appeared to use
+# U+0028 LEFT PARENTHESIS for this purpose.)
+
+# Auto-Detect (sub)menu
+charsetMenuCharsets = Nodau Amgodio
+charsetMenuAutodet = Awto-Ganfod
+# 'A' is reserved for Arabic:
+charsetMenuAutodet.key = D
+charsetMenuAutodet.off = (diffodd)
+charsetMenuAutodet.off.key = o
+charsetMenuAutodet.ru = Rwseg
+charsetMenuAutodet.ru.key = R
+charsetMenuAutodet.uk = Wcraneg
+charsetMenuAutodet.uk.key = U
+
+# Globally-relevant
+
+_autodetect_all.key =     m
+_autodetect_all     = Awtomatig
+UTF-8.key        = U
+UTF-8            = Unicode
+windows-1252.key = W
+windows-1252     = Gorllewinol
+
+# Arabic
+windows-1256.key = A
+windows-1256     = Arabaidd (Windows)
+ISO-8859-6       = Arabaidd (ISO)
+
+# Baltic
+windows-1257.key = B
+windows-1257     = Baltig (Windows)
+ISO-8859-4       = Baltig (ISO)
+
+# Central European
+windows-1250.key =         E
+windows-1250     = Canol Ewrop (Windows)
+ISO-8859-2.key   =       l
+ISO-8859-2       = Canol Ewrop (ISO)
+
+# Chinese, Simplified
+gbk.bis.key      =          S
+gbk.bis          = Tsieinëeg, Symledig
+
+# Chinese, Traditional
+Big5.key         =          T
+Big5             = Tsieinëeg Traddodiadol
+
+# Cyrillic
+windows-1251.key = C
+windows-1251     = Cyrilig (Windows)
+ISO-8859-5       = Cyrilig (ISO)
+KOI8-R           = Cyrilig (KOI8-R)
+KOI8-U           = Cyrilig (KOI8-U)
+IBM866           = Cyrilig (DOS)
+
+# UI string in anticipation of Cyrillic analog of bug 1543077;
+# deliberately not in use yet
+
+# LOCALIZATION NOTE (Cyrillic.key): If taken into use, this string will appear
+# instead of the string for windows-1251.key, so the use of the same
+# accelerator is deliberate.
+Cyrillic.key     = T
+# LOCALIZATION NOTE (Cyrillic): If taken into use, this string will appear
+# as a single item instead of the five items windows-1251, ISO-8859-5,
+# KOI8-R, KOI8-U, and IBM866, so this string does not need to make sense
+# together with those strings and should be translated the way those were
+# but omitting the part in parentheses.
+Cyrillic         = Cyrilig
+
+# Greek
+windows-1253.key = G
+windows-1253     = Groeg (Windows)
+ISO-8859-7.key   =          O
+ISO-8859-7       = Groeg (ISO)
+
+# Hebrew
+windows-1255.key = H
+windows-1255     = Hebraeg
+# LOCALIZATION NOTE (ISO-8859-8): The value for this item should begin with
+# the same word for Hebrew as the value for windows-1255 so that this item
+# sorts right after that one in the collation order for your locale.
+ISO-8859-8       = Hebraeg, Gweledol
+
+# Japanese (NOT AN ENCODING NAME)
+Japanese.key     = J
+Japanese         = Japanëeg
+
+# Korean
+EUC-KR.key       = o
+EUC-KR           = Corëeg
+
+# Thai
+windows-874.key  =    i
+windows-874      = Thai
+
+# Turkish
+windows-1254.key =   r
+windows-1254     = Twrceg
+
+# Vietnamese
+windows-1258.key = F
+windows-1258     = Fietnamaidd
+
diff --git a/l10n-cy/toolkit/chrome/global/commonDialog.dtd b/l10n-cy/toolkit/chrome/global/commonDialog.dtd
new file mode 100644
index 0000000000..9dfdb74282
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/commonDialog.dtd
@@ -0,0 +1,10 @@
+<!-- This Source Code Form is subject to the terms of the Mozilla Public
+   - License, v. 2.0. If a copy of the MPL was not distributed with this
+   - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
+
+<!ENTITY editfield0.label "Enw Defnyddiwr:"> 
+<!ENTITY editfield1.label "Cyfrinair:"> 
+<!ENTITY copyCmd.label    "Copïo">
+<!ENTITY copyCmd.accesskey "C">
+<!ENTITY selectAllCmd.label "Dewis Popeth">
+<!ENTITY selectAllCmd.accesskey "P">
diff --git a/l10n-cy/toolkit/chrome/global/commonDialogs.properties b/l10n-cy/toolkit/chrome/global/commonDialogs.properties
new file mode 100644
index 0000000000..8a3efbb7ca
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/commonDialogs.properties
@@ -0,0 +1,34 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+Alert=Rhybudd
+Confirm=Cadarnhau
+ConfirmCheck=Cadarnhau
+Prompt=Anogiad
+# LOCALIZATION NOTE - %S is brandFullName
+PromptUsernameAndPassword3=Angen Dilysu - %S
+# LOCALIZATION NOTE - %S is brandFullName
+PromptPassword3=Angen Cyfrinair - %S
+Select=Dewis
+OK=Iawn
+Cancel=Diddymu
+Yes=&Iawn
+No=&Na
+Save=&Cadw
+Revert=&Dychwelyd
+DontSave=&Peidio â Chadw
+ScriptDlgGenericHeading=[Rhaglen JavaScript]
+ScriptDlgHeading=Mae tudalen %S yn dweud:
+ScriptDialogLabel=Atal y dudalen hon rhag creu deialogau ychwanegol
+ScriptDialogPreventTitle=Cadarnhau Dewisiadau Deialog
+# LOCALIZATION NOTE (EnterLoginForRealm3, EnterLoginForProxy3):
+# %1 is an untrusted string provided by a remote server. It could try to
+# take advantage of sentence structure in order to mislead the user (see
+# bug 244273). %1 should be integrated into the translated sentences as
+# little as possible. %2 is the url of the site being accessed.
+EnterLoginForRealm3=Mae %2$S yn gofyn am enw defnyddiwr a chyfrinair. Mae'r wefan yn dweud: “%1$S”
+EnterLoginForProxy3=Mae'r dirprwy %2$S yn gofyn am enw defnyddiwr a chyfrinair. Mae'r wefan yn dweud: “%1$S”
+EnterUserPasswordFor2=Mae %1$S yn gofyn am enw defnyddiwr a chyfrinair.
+EnterUserPasswordForCrossOrigin2=Mae %1$S yn gofyn am enw defnyddiwr a chyfrinair. RHYBUDD: Ni fydd eich cyfrinair yn cael ei anfon at y wefan rydych arni ar hyn o bryd!
+EnterPasswordFor=Rhowch gyfrinair ar gyfer %1$S ar %2$S
diff --git a/l10n-cy/toolkit/chrome/global/contentAreaCommands.properties b/l10n-cy/toolkit/chrome/global/contentAreaCommands.properties
new file mode 100644
index 0000000000..57347dc4b5
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/contentAreaCommands.properties
@@ -0,0 +1,23 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# context menu strings
+
+SaveImageTitle=Cadw Delwedd
+SaveMediaTitle=Cadw'r Cyfryngau
+SaveVideoTitle=Cadw Fideo
+SaveAudioTitle=Cadw Sain
+SaveLinkTitle=Cadw Fel
+DefaultSaveFileName=mynegai
+WebPageCompleteFilter=Tudalen We, yn gyfan
+WebPageHTMLOnlyFilter=Tudalen We, HTML yn unig
+WebPageXHTMLOnlyFilter=Tudalen Gwe, XHTML yn unig
+WebPageSVGOnlyFilter=Tudalen gwe, SVG yn unig
+WebPageXMLOnlyFilter=Tudalen Gwe XML yn unig
+
+# LOCALIZATION NOTE (filesFolder):
+#    This is the name of the folder that is created parallel to a HTML file 
+#    when it is saved "With Images". The %S section is replaced with the
+#    leaf name of the file being saved (minus extension).
+filesFolder=%S_files
diff --git a/l10n-cy/toolkit/chrome/global/datetimebox.dtd b/l10n-cy/toolkit/chrome/global/datetimebox.dtd
new file mode 100644
index 0000000000..cc9d7f6ff3
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/datetimebox.dtd
@@ -0,0 +1,35 @@
+<!-- This Source Code Form is subject to the terms of the Mozilla Public
+   - License, v. 2.0. If a copy of the MPL was not distributed with this
+   - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
+
+<!-- Placeholders for input type=time -->
+
+<!ENTITY time.hour.placeholder "--">
+<!ENTITY time.minute.placeholder "--">
+<!ENTITY time.second.placeholder "--">
+<!ENTITY time.millisecond.placeholder "--">
+<!ENTITY time.dayperiod.placeholder "--">
+
+<!-- Field labels for input type=time -->
+
+<!ENTITY time.hour.label "Awr">
+<!ENTITY time.minute.label "Munud">
+<!ENTITY time.second.label "Eiliad">
+<!ENTITY time.millisecond.label "Milieiliad">
+<!ENTITY time.dayperiod.label "AM/PM">
+
+<!-- Placeholders for input type=date -->
+
+<!ENTITY date.year.placeholder "bbbb">
+<!ENTITY date.month.placeholder "mm">
+<!ENTITY date.day.placeholder "dd">
+
+<!-- Field labels for input type=date -->
+
+<!ENTITY date.year.label "Blwyddyn">
+<!ENTITY date.month.label "Mis">
+<!ENTITY date.day.label "Diwrnod">
+
+<!-- Date/time clear button -->
+
+<!ENTITY datetime.reset.label "Clirio">
diff --git a/l10n-cy/toolkit/chrome/global/dialog.properties b/l10n-cy/toolkit/chrome/global/dialog.properties
new file mode 100644
index 0000000000..86e5831f32
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/dialog.properties
@@ -0,0 +1,12 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+button-accept=Iawn
+button-cancel=Diddymu
+button-help=Cymorth
+button-disclosure=Rhagor o Wybodaeth
+accesskey-accept=
+accesskey-cancel=
+accesskey-help=C
+accesskey-disclosure=D
diff --git a/l10n-cy/toolkit/chrome/global/dialogOverlay.dtd b/l10n-cy/toolkit/chrome/global/dialogOverlay.dtd
new file mode 100644
index 0000000000..1b0def64e8
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/dialogOverlay.dtd
@@ -0,0 +1,10 @@
+<!-- This Source Code Form is subject to the terms of the Mozilla Public
+   - License, v. 2.0. If a copy of the MPL was not distributed with this
+   - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
+
+<!-- WARNING!!! This file is obsoleted by the dialog.xml widget -->
+<!-- OK Cancel Buttons -->
+
+
+<!ENTITY okButton.label      "Iawn">
+<!ENTITY cancelButton.label  "Diddymu">
diff --git a/l10n-cy/toolkit/chrome/global/editMenuOverlay.dtd b/l10n-cy/toolkit/chrome/global/editMenuOverlay.dtd
new file mode 100644
index 0000000000..b3fd3f63cc
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/editMenuOverlay.dtd
@@ -0,0 +1,11 @@
+<!-- This Source Code Form is subject to the terms of the Mozilla Public
+   - License, v. 2.0. If a copy of the MPL was not distributed with this
+   - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
+
+<!ENTITY findCmd.label             "Canfod">
+<!ENTITY findCmd.key               "F">
+<!ENTITY findCmd.accesskey         "f">
+<!ENTITY findAgainCmd.label        "Canfod Eto">
+<!ENTITY findAgainCmd.key          "G">
+<!ENTITY findAgainCmd.key2         "VK_F3">
+<!ENTITY findAgainCmd.accesskey    "a">
diff --git a/l10n-cy/toolkit/chrome/global/extensions.properties b/l10n-cy/toolkit/chrome/global/extensions.properties
new file mode 100644
index 0000000000..2cfa1518c4
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/extensions.properties
@@ -0,0 +1,44 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+csp.error.missing-directive = Nid yw'r polisi'n cynnwys cyfarwyddeb '%S' angenrheidiol
+
+#LOCALIZATION NOTE (csp.error.illegal-keyword) %1$S is the name of a CSP directive, such as "script-src". %2$S is the name of a CSP keyword, usually 'unsafe-inline'.
+csp.error.illegal-keyword = Mae '%1$S' yn cynnwys cyfarwyddeb gwaharddedig allweddair %2$S
+
+#LOCALIZATION NOTE (csp.error.illegal-protocol) %2$S a protocol name, such as "http", which appears as "http:", as it would in a URL.
+csp.error.illegal-protocol = Mae '%1$S' yn cynnwys cyfarwyddeb gwaharddedig %2$S: protocol ffynhonnell
+
+#LOCALIZATION NOTE (csp.error.missing-host) %2$S a protocol name, such as "http", which appears as "http:", as it would in a URL.
+csp.error.missing-host = %2$S: mae'r protocol angen gwestai mewn cyfarwyddeb '%1$S'
+
+#LOCALIZATION NOTE (csp.error.missing-source) %1$S is the name of a CSP directive, such as "script-src". %2$S is the name of a CSP source, usually 'self'.
+csp.error.missing-source = Rhaid i '%1$S' gynnwys y ffynhonnell %2$S
+
+#LOCALIZATION NOTE (csp.error.illegal-host-wildcard) %2$S a protocol name, such as "http", which appears as "http:", as it would in a URL.
+csp.error.illegal-host-wildcard = %2$S: rhaid i ffynonellau cerdyn gwyllt o fewn cyfarwyddeb '%1$S' gynnwys o leiaf un isbarth generig (e.e., *.example.com yn lle *.com)
+
+#LOCALIZATION NOTE (uninstall.confirmation.title) %S is the name of the extension which is about to be uninstalled.
+uninstall.confirmation.title = Dadosod %S
+
+#LOCALIZATION NOTE (uninstall.confirmation.message) %S is the name of the extension which is about to be uninstalled.
+uninstall.confirmation.message = Mae estyniad “%S” yn gofyn am gael ei ddadosod. Beth hoffech chi ei wneud?
+
+uninstall.confirmation.button-0.label = Dadosod
+uninstall.confirmation.button-1.label = Cadw Wedi ei Osod
+
+saveaspdf.saveasdialog.title = Cadw Fel
+
+#LOCALIZATION NOTE (newTabControlled.message2) %S is the icon and name of the extension which updated the New Tab page.
+newTabControlled.message2 = Mae'r estyniad %S, wedi newid y ffenestr rydych yn ei weld pan fyddwch yn agor tab newydd.
+newTabControlled.learnMore = Dysgu rhagor
+
+#LOCALIZATION NOTE (homepageControlled.message) %S is the icon and name of the extension which updated the homepage.
+homepageControlled.message = Mae'r estyniad %S, wedi newid yr hyn rydych yn ei weld pan fyddwch yn agor eich tudalen cartref a ffenestri newydd.
+homepageControlled.learnMore = Dysgu rhagor
+
+#LOCALIZATION NOTE (tabHideControlled.message) %1$S is the icon and name of the extension which hid tabs, %2$S is the icon of the all tabs button.
+tabHideControlled.message = Mae estyniad, %1$S, yn cuddio rhai o'ch tabiau. Gallwch gael mynediad i'ch holl dabiau o %2$S.
+tabHideControlled.learnMore = Dysgu rhagor
+
diff --git a/l10n-cy/toolkit/chrome/global/fallbackMenubar.properties b/l10n-cy/toolkit/chrome/global/fallbackMenubar.properties
new file mode 100644
index 0000000000..83d9b7a9a3
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/fallbackMenubar.properties
@@ -0,0 +1,8 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# OSX only. Default menu label when there is no xul menubar.
+
+quitMenuitem.label=Gadael
+quitMenuitem.key=q
diff --git a/l10n-cy/toolkit/chrome/global/filepicker.properties b/l10n-cy/toolkit/chrome/global/filepicker.properties
new file mode 100644
index 0000000000..bd041ca71f
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/filepicker.properties
@@ -0,0 +1,18 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# LOCALIZATION NOTE: The extensions to which these descriptions refer
+#                    now live in toolkit/content/filepicker.properties
+allTitle=Pob Ffeil
+htmlTitle=Ffeiliau HTML
+textTitle=Ffeiliau Testun
+imageTitle=Ffeiliau Delwedd
+xmlTitle=Ffeiliau XML
+xulTitle=Ffeiliau XUL
+appsTitle=Rhaglenni
+audioTitle=Ffeiliau Sain
+videoTitle=Ffeiliau Fideo
+
+formatLabel=Fformat:
+
diff --git a/l10n-cy/toolkit/chrome/global/findbar.properties b/l10n-cy/toolkit/chrome/global/findbar.properties
new file mode 100644
index 0000000000..3ec01b8b53
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/findbar.properties
@@ -0,0 +1,23 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# strings used by the Find bar, split from browser.properties
+NotFound=Heb ganfod ymadrodd
+WrappedToTop=Wedi cyrraedd diwedd y dudalen, parhau o'r brig
+WrappedToBottom=Wedi cyrraedd diwedd y dudalen, parhau o'r gwaelod
+NormalFind=Canfod ar y dudalen
+FastFind=Canfod cyflym
+FastFindLinks=Canfod cyflym (dolenni'n unig)
+CaseSensitive=(Mawr/bach)
+MatchDiacritics=(Diacritig cyfatebol)
+EntireWord=(Geiriau llawn yn unig)
+# LOCALIZATION NOTE (FoundMatches): Semicolon-separated list of plural forms.
+# See: http://developer.mozilla.org/en/docs/Localization_and_Plurals
+# #1 is currently selected match and #2 the total amount of matches.
+FoundMatches=Dim cydweddiadau;#1 o #2 cydweddiad;#1 o #2 gydweddiad;#1 o #2 cydweddiad;#1 o #2 chydweddiad;#1 o #2 cydweddiad
+# LOCALIZATION NOTE (FoundMatchesCountLimit): Semicolon-separated list of plural
+# forms.
+# See: http://developer.mozilla.org/en/docs/Localization_and_Plurals
+# #1 is the total amount of matches allowed before counting stops.
+FoundMatchesCountLimit=Dim cydweddiadau;Mwy nag #1 cydweddiad;Mwy na #1 gydweddiad;Mwy nag #1 chydweddiad;Mwy nag #1 chydweddiad;Mwy nag #1 cydweddiad
diff --git a/l10n-cy/toolkit/chrome/global/global-extension-fields.properties b/l10n-cy/toolkit/chrome/global/global-extension-fields.properties
new file mode 100644
index 0000000000..6eb474268d
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/global-extension-fields.properties
@@ -0,0 +1,8 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# LOCALIZATION NOTE (extension.default-theme@mozilla.org.name, extension.default-theme@mozilla.org.description): This is displayed in about:addons -> Appearance
+extension.default-theme@mozilla.org.name=Rhagosodiad
+extension.default-theme@mozilla.org.description=Thema sydd â chynllun lliw'r system weithredu.
+
diff --git a/l10n-cy/toolkit/chrome/global/globalKeys.dtd b/l10n-cy/toolkit/chrome/global/globalKeys.dtd
new file mode 100644
index 0000000000..76b9235713
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/globalKeys.dtd
@@ -0,0 +1,6 @@
+<!-- This Source Code Form is subject to the terms of the Mozilla Public
+   - License, v. 2.0. If a copy of the MPL was not distributed with this
+   - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
+
+<!ENTITY openHelp.commandkey     "VK_F1">
+<!ENTITY openHelpMac.commandkey  "?">
diff --git a/l10n-cy/toolkit/chrome/global/intl.css b/l10n-cy/toolkit/chrome/global/intl.css
new file mode 100644
index 0000000000..0221f963e1
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/intl.css
@@ -0,0 +1,7 @@
+/*
+ * This file contains all localizable skin settings such as 
+ *   font, layout, and geometry
+ */
+window { 
+  font: 3mm tahoma,arial,helvetica,sans-serif;
+}
diff --git a/l10n-cy/toolkit/chrome/global/intl.properties b/l10n-cy/toolkit/chrome/global/intl.properties
new file mode 100644
index 0000000000..e47e1a993e
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/intl.properties
@@ -0,0 +1,51 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# LOCALIZATION NOTE (intl.accept_languages):
+# This is a comma-separated list of valid BCP 47 language tags.
+#
+# Begin with the language tag of your locale. Next, include language
+# tags for other languages that you expect most users of your locale to be
+# able to speak, so that their browsing experience degrades gracefully if
+# content is not available in their primary language.
+#
+# It is recommended that you include "en-US, en" at the end of the list as a
+# last resort. However, if you know that users of your locale would prefer a
+# different variety of English, or if they are not likely to understand
+# English at all, you may opt to include a different English language tag, or
+# to exclude English altogether.
+#
+# For example, the Breton [br] locale might consider including French and
+# British English in their list, since those languages are commonly spoken in
+# the same area as Breton:
+# intl.accept_languages=br, fr-FR, fr, en-GB, en
+intl.accept_languages=cy-GB, cy, en-US, en
+
+# LOCALIZATION NOTE (font.language.group):
+# This preference controls the initial setting of the language drop-down menu
+# in the Content > Fonts & Colors > Advanced preference panel.
+#
+# Set it to the value of one of the menuitems in the "selectLangs" menulist in
+# http://dxr.mozilla.org/mozilla-central/source/browser/components/preferences/fonts.xul
+font.language.group=x-western
+
+# LOCALIZATION NOTE (intl.charset.detector):
+# This preference controls the initial setting for the character encoding
+# detector. Valid values are ja_parallel_state_machine for Japanese, ruprob
+# for Russian and ukprob for Ukrainian and the empty string to turn detection
+# off. The value must be empty for locales other than Japanese, Russian and
+# Ukrainian.
+intl.charset.detector=
+
+# LOCALIZATION NOTE (pluralRule): Pick the appropriate plural rule for your
+# language. This will determine how many plural forms of a word you will need
+# to provide and in what order.
+# See: http://developer.mozilla.org/en/docs/Localization_and_Plurals
+pluralRule=18
+
+# LOCALIZATION NOTE (intl.menuitems.alwaysappendaccesskeys, intl.menuitems.insertseparatorbeforeaccesskeys):
+# Valid values are: true, false, <empty string>
+# Missing preference or empty value equals false.
+intl.menuitems.alwaysappendaccesskeys=
+intl.menuitems.insertseparatorbeforeaccesskeys=true
diff --git a/l10n-cy/toolkit/chrome/global/keys.properties b/l10n-cy/toolkit/chrome/global/keys.properties
new file mode 100644
index 0000000000..0ca2e8c223
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/keys.properties
@@ -0,0 +1,78 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# LOCALIZATION NOTE : FILE This file contains the application's labels for keys on the keyboard.
+#                     If you decide to translate this file, you should translate it based on
+#                     the prevelant kind of keyboard for your target user.
+# LOCALIZATION NOTE : There are two types of keys, those w/ text on their labels
+#                     and those w/ glyphs.
+# LOCALIZATION NOTE : VK_<…> represents a key on the keyboard.
+#
+# For more information please see bugzilla bug 90888.
+
+# LOCALIZATION NOTE : FILE This file contains the application's labels for keys on the keyboard.
+#                     If you decide to translate this file, you should translate it based on
+#                     the prevalent kind of keyboard for your target user.
+# LOCALIZATION NOTE : There are two types of keys, those w/ text on their labels
+#                     and those w/ glyphs.
+# LOCALIZATION NOTE : VK_<…> represents a key on the keyboard.
+#
+# For more information please see bugzilla bug 90888.
+
+# F1..F10 should probably not be translated unless there are keyboards that actually have other labels
+# F11..F20 might be something else, but are really keyboard specific and not region/language specific
+# there are actually two different F11/F12 keys, I don't know which one these labels represent.
+# eg, F13..F20 on a sparc keyboard are labeled Props, Again .. Find, Cut
+# sparc also has Stop, Again and F11/F12. VK_F11/VK_F12 probably map to Stop/Again
+# LOCALIZATION NOTE : BLOCK Do not translate the next block
+VK_F1=F1
+VK_F2=F2
+VK_F3=F3
+VK_F4=F4
+VK_F5=F5
+VK_F6=F6
+VK_F7=F7
+VK_F8=F8
+VK_F9=F9
+VK_F10=F10
+
+VK_F11=F11
+VK_F12=F12
+VK_F13=F13
+VK_F14=F14
+VK_F15=F15
+VK_F16=F16
+VK_F17=F17
+VK_F18=F18
+VK_F19=F19
+VK_F20=F20
+# LOCALIZATION NOTE : BLOCK end do not translate block
+
+# LOCALIZATION NOTE : BLOCK GLYPHS, DO translate this block
+VK_UP=Saeth i Fyny
+VK_DOWN=Saeth i Lawr
+VK_LEFT=Saeth i'r Chwith
+VK_RIGHT=Saeth i'r Dde
+VK_PAGE_UP=Page Up
+VK_PAGE_DOWN=Page Down
+# LOCALIZATION NOTE : BLOCK end GLYPHS
+
+# Enter, backspace, and Tab might have both glyphs and text
+# if the keyboards usually have a glyph,
+# if there is a meaningful translation,
+# or if keyboards are localized
+# then translate them or insert the appropriate glyph
+# otherwise you should probably just translate the glyph regions
+
+VK_TAB=Tab
+VK_BACK=Backspace
+VK_DELETE=Del
+# LOCALIZATION NOTE : BLOCK end maybe GLYPHS
+# LOCALIZATION NOTE : BLOCK typing state keys
+VK_HOME=Home
+VK_END=End
+
+VK_ESCAPE=Esc
+VK_INSERT=Ins
+# LOCALIZATION NOTE : BLOCK end
diff --git a/l10n-cy/toolkit/chrome/global/mozilla.dtd b/l10n-cy/toolkit/chrome/global/mozilla.dtd
new file mode 100644
index 0000000000..8de8d39616
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/mozilla.dtd
@@ -0,0 +1,14 @@
+<!-- This Source Code Form is subject to the terms of the Mozilla Public
+   - License, v. 2.0. If a copy of the MPL was not distributed with this
+   - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
+
+<!ENTITY mozilla.title.11.14
+'Llyfr Mozilla, 11:14'>
+
+<!ENTITY mozilla.quote.11.14
+"Gwisgodd yr Anghenfil <em>ddillad newydd</em> ac astudio ffyrdd <em>Amser</em> a't <em>Gofod</em> 
+a't <em>Golau</em> a'r <em>Llif</em> egni drwy'r Bydysawd. O'i astudiaethau, lluniodd yr Anghenfil strwythurau newydd o <em>fetel wedi ei ocsideiddio</em> a datgan eu gogoniant.
+Llawenychodd dilynwyr yr Anghenfil, gan ganfod pwrpas newydd yn y <em>dysgeidiaethau</em> hyn.">
+
+<!ENTITY mozilla.from.11.14
+'o<strong>Lyfr Mozilla,</strong> 11:14'>
diff --git a/l10n-cy/toolkit/chrome/global/narrate.properties b/l10n-cy/toolkit/chrome/global/narrate.properties
new file mode 100644
index 0000000000..e63b29f667
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/narrate.properties
@@ -0,0 +1,20 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# "Listen, which allows users to listen to Firefox reading the text, 
+# instead of having to read it themselves." This is the name
+# of the feature and it is the label for the popup button.
+listen = Gwrando
+back = Nôl
+start = Cychwyn
+stop = Atal
+forward = Ymlaen
+speed = Cyflymder
+selectvoicelabel = Llais:
+# Default voice is determined by the language of the document.
+defaultvoice = Rhagosodiad
+
+# Voice name and language.
+# eg. David (English)
+voiceLabel = %S (%S)
diff --git a/l10n-cy/toolkit/chrome/global/notification.dtd b/l10n-cy/toolkit/chrome/global/notification.dtd
new file mode 100644
index 0000000000..330d90cad4
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/notification.dtd
@@ -0,0 +1,14 @@
+<!-- This Source Code Form is subject to the terms of the Mozilla Public
+   - License, v. 2.0. If a copy of the MPL was not distributed with this
+   - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
+
+<!ENTITY closeNotification.tooltip "Cau'r neges hon">
+
+<!ENTITY checkForUpdates "Gwirio am ddiweddariadau…">
+
+<!ENTITY learnMoreNoEllipsis "Dysgu rhagor">
+
+<!ENTITY defaultButton.label "Iawn!">
+<!ENTITY defaultButton.accesskey "I">
+
+<!ENTITY moreActionsButton.accessibleLabel "Rhagor o weithredoedd">
diff --git a/l10n-cy/toolkit/chrome/global/printdialog.properties b/l10n-cy/toolkit/chrome/global/printdialog.properties
new file mode 100644
index 0000000000..a0930388e5
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/printdialog.properties
@@ -0,0 +1,52 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# These strings are used in the native GTK, Mac and Windows print dialogs.
+
+# GTK titles:
+printTitleGTK=Argraffu
+optionsTabLabelGTK=Dewisiadau
+
+# Mac titles:
+optionsTitleMac=Dewisiadau:
+appearanceTitleMac=Golwg:
+pageHeadersTitleMac=Penawdau Tudalen:
+pageFootersTitleMac=Troedyn Tudalen:
+
+# Windows titles:
+optionsTitleWindows=Dewisiadau
+
+# TRANSLATOR NOTE: For radio button labels and check button labels, an underscore _
+# before a character will turn that character into an accesskey in the GTK dialog.
+# e.g. "_As laid out" will make A the accesskey.
+# In the Windows labels, use an ampersand (&).
+# On Mac, underscores will be stripped.
+
+shrinkToFit=Anwybyddu Graddio a _Lleihau i Ffitio Lled y Dudalen
+selectionOnly=Argraffu'r Dewis yn _Unig
+printBGOptions=Argraffu Cefndiroedd
+printBGColors=Argraffu _Lliwiau Cefndiroedd
+printBGImages=Argraffu _Delweddau Cefndir
+headerFooter=Pennyn a Throedyn
+left=Chwith
+center=Canol
+right=De
+headerFooterBlank=--gwag--
+headerFooterTitle=Teitl
+headerFooterURL=URL
+headerFooterDate=Dyddiad/Amser
+headerFooterPage=Tudalen #
+headerFooterPageTotal=Tudalen # o #
+headerFooterCustom=Cyfaddasu…
+customHeaderFooterPrompt=Rhowch destun eich pennyn/troedyn cyfaddas
+
+summarySelectionOnlyTitle=Dewis Argraffu
+summaryShrinkToFitTitle=Lleihau i'r Maint
+summaryPrintBGColorsTitle=Argraffu Lliwiau BG
+summaryPrintBGImagesTitle=Argraffu Delweddau BG
+summaryHeaderTitle=Pennyn Tudalen
+summaryFooterTitle=Troedyn Tudalen
+summaryNAValue=Dim
+summaryOnValue=Ymlaen
+summaryOffValue=Diffodd
diff --git a/l10n-cy/toolkit/chrome/global/resetProfile.dtd b/l10n-cy/toolkit/chrome/global/resetProfile.dtd
new file mode 100644
index 0000000000..426103ba1e
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/resetProfile.dtd
@@ -0,0 +1,7 @@
+<!-- This Source Code Form is subject to the terms of the Mozilla Public
+   - License, v. 2.0. If a copy of the MPL was not distributed with this file,
+   - You can obtain one at http://mozilla.org/MPL/2.0/.  -->
+
+<!ENTITY refreshProfile.dialog.title         "Adnewyddu &brandShortName;">
+
+<!ENTITY refreshProfile.cleaning.description "Bron â gorffen…">
diff --git a/l10n-cy/toolkit/chrome/global/resetProfile.properties b/l10n-cy/toolkit/chrome/global/resetProfile.properties
new file mode 100644
index 0000000000..98af519292
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/resetProfile.properties
@@ -0,0 +1,14 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# LOCALIZATION NOTE: These strings are used for profile reset.
+
+# LOCALIZATION NOTE (resetUnusedProfile.message): %S is brandShortName.
+resetUnusedProfile.message=Mae'n edrych fel nad ydych wedi cychwyn %S ers tro. Hoffech chi ei lanhau ar gyfer profiad fel newydd? A gyda llaw, croeso nôl!
+# LOCALIZATION NOTE (resetUninstalled.message): %S is brandShortName.
+resetUninstalled.message=Mae'n edrych fel eich bod wedi ailosod %S. Hoffech chi ei lanhau ar gyfer profiad fel newydd?
+
+# LOCALIZATION NOTE (refreshProfile.resetButton.label): %S is brandShortName.
+refreshProfile.resetButton.label=Adnewyddu %S…
+refreshProfile.resetButton.accesskey=A
diff --git a/l10n-cy/toolkit/chrome/global/textcontext.dtd b/l10n-cy/toolkit/chrome/global/textcontext.dtd
new file mode 100644
index 0000000000..29edb91650
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/textcontext.dtd
@@ -0,0 +1,24 @@
+<!-- This Source Code Form is subject to the terms of the Mozilla Public
+   - License, v. 2.0. If a copy of the MPL was not distributed with this
+   - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
+
+<!ENTITY spellAddToDictionary.label "Ychwanegu at y Geiriadur">
+<!ENTITY spellAddToDictionary.accesskey "Y">
+<!ENTITY spellUndoAddToDictionary.label "Dadwneud Ychwanegu at y Geiriadur">
+<!ENTITY spellUndoAddToDictionary.accesskey "D">
+<!ENTITY spellCheckToggle.label "Gwirio Sillafu">
+<!ENTITY spellCheckToggle.accesskey "G">
+<!ENTITY spellNoSuggestions.label "(Dim Awgrymiadau Sillafu)">
+<!ENTITY spellDictionaries.label "Ieithoedd">
+<!ENTITY spellDictionaries.accesskey "I">
+
+<!ENTITY searchTextBox.clear.label "Clirio">
+
+<!ENTITY fillLoginMenu.label          "Llanw'r Mewngofnodi">
+<!ENTITY fillLoginMenu.accesskey      "L">
+<!ENTITY fillPasswordMenu.label       "Llanw'r Cyfrinair">
+<!ENTITY fillPasswordMenu.accesskey   "L">
+<!ENTITY fillUsernameMenu.label       "Llanw'r Enw Defnyddiwr">
+<!ENTITY fillUsernameMenu.accesskey   "L">
+<!ENTITY noLoginSuggestions.label     "(Dim Awgrymiadau Mewngofnodi)">
+<!ENTITY viewSavedLogins.label        "Gweld y Mewngofnodi Lanwyd">
diff --git a/l10n-cy/toolkit/chrome/global/tree.dtd b/l10n-cy/toolkit/chrome/global/tree.dtd
new file mode 100644
index 0000000000..87e119aa63
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/tree.dtd
@@ -0,0 +1,5 @@
+<!-- This Source Code Form is subject to the terms of the Mozilla Public
+   - License, v. 2.0. If a copy of the MPL was not distributed with this
+   - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
+
+<!ENTITY restoreColumnOrder.label "Adfer Trefn Colofnau">
diff --git a/l10n-cy/toolkit/chrome/global/videocontrols.dtd b/l10n-cy/toolkit/chrome/global/videocontrols.dtd
new file mode 100644
index 0000000000..d01e9a4793
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/videocontrols.dtd
@@ -0,0 +1,52 @@
+<!-- This Source Code Form is subject to the terms of the Mozilla Public
+   - License, v. 2.0. If a copy of the MPL was not distributed with this
+   - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
+
+<!ENTITY % brandDTD
+    SYSTEM "chrome://branding/locale/brand.dtd">
+  %brandDTD;
+
+<!ENTITY playButton.playLabel "Chwarae">
+<!ENTITY playButton.pauseLabel "Oedi">
+<!ENTITY muteButton.muteLabel "Tewi">
+<!ENTITY muteButton.unmuteLabel "Dad dewi">
+<!ENTITY fullscreenButton.enterfullscreenlabel "Sgrin Lawn">
+<!ENTITY fullscreenButton.exitfullscreenlabel "Gadael y Sgrin Lawn">
+<!ENTITY castingButton.castingLabel "Darlledu i'r Sgrin">
+<!ENTITY closedCaption.off "Diffodd">
+<!-- LOCALIZATION NOTE (volumeScrubber.label): This label is exposed to
+     accessibility software to clarify what the slider is for. -->
+<!ENTITY volumeScrubber.label "Llithrydd sain">
+
+<!-- LOCALIZATION NOTE (pictureInPicture.label): This string is used as part of
+the Picture-in-Picture video toggle button when the mouse is hovering it. -->
+<!ENTITY pictureInPicture.label "Llun mewn Llun">
+
+<!-- LOCALIZATION NOTE (pictureInPictureToggle.label): This string is used as the
+label for a variation of the Picture-in-Picture video toggle button when the mouse is
+hovering over the video. -->
+<!ENTITY pictureInPictureToggle.label "Gwylio yn Llun-mewn-Llun">
+<!-- LOCALIZATION NOTE (pictureInPictureExplainer): This string is used as part of
+a variation of the Picture-in-Picture video toggle button. When using this variation,
+this string appears below the toggle when the mouse hovers the toggle. -->
+<!ENTITY pictureInPictureExplainer "Gwylio fideos yn y blaendir tra'ch bod chi'n gwneud pethau eraill gyda &brandShortName;">
+
+<!ENTITY error.aborted "Mae llwytho'r fideo wedi dod i ben.">
+<!ENTITY error.network "Mae chwarae'r fideo wedi dod i ben oherwydd gwall rhwydwaith.">
+<!ENTITY error.decode "Nid oedd modd chwarae'r fideo gan fod y ffeil yn llwgr.">
+<!ENTITY error.srcNotSupported "Nid yw'r fformat fideo na'r math MIME yn cael eu cynnal.">
+<!ENTITY error.noSource2 "Heb ganfod fideo gyda fformat sy'n cael ei gynnal na math MIME.">
+<!ENTITY error.generic "Ataliwyd chwarae'r fideo oherwydd gwall anhysbys.">
+
+<!ENTITY status.pictureInPicture "Mae'r fideo hwn yn chwarae yn y modd Llun mewn Llun.">
+
+<!-- LOCALIZATION NOTE (positionAndDuration.nameFormat): the #1 string is the current
+media position, and the #2 string is the total duration. For example, when at
+the 5 minute mark in a 6 hour long video, #1 would be "5:00" and #2 would be
+"6:00:00", result string would be "5:00 / 6:00:00".
+Note that #2 is not always available. For example, when at the 5 minute mark in an
+unknown duration video, #1 would be "5:00" and the string which is surrounded by
+<span> would be deleted, result string would be "5:00".
+-->
+<!ENTITY positionAndDuration.nameFormat "#1<span> / #2</span>">
+
diff --git a/l10n-cy/toolkit/chrome/global/viewSource.properties b/l10n-cy/toolkit/chrome/global/viewSource.properties
new file mode 100644
index 0000000000..a29544bd7a
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/viewSource.properties
@@ -0,0 +1,16 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+goToLineTitle     = Mynd i'r llinell
+goToLineText      = Rhowch rif y llinell
+invalidInputTitle = Mewnbwn annilys
+invalidInputText  = Mae'r rhif roddwyd yn annilys.
+outOfRangeTitle   = Heb ganfod y llinell
+outOfRangeText    = Heb ganfod y linell hon.
+viewSelectionSourceTitle = Ffynhonnell DOM Dewis
+
+context_goToLine_label        = Mynd i Linell…
+context_goToLine_accesskey    = L
+context_wrapLongLines_label   = Amlapio Llinellau Hir
+context_highlightSyntax_label = Amlygu Cystrawen
diff --git a/l10n-cy/toolkit/chrome/global/wizard.properties b/l10n-cy/toolkit/chrome/global/wizard.properties
new file mode 100644
index 0000000000..a84087d2ac
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/global/wizard.properties
@@ -0,0 +1,8 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+default-first-title=Croeso i %S
+default-last-title=Cwblhau %S
+default-first-title-mac=Cyflwyniad
+default-last-title-mac=Diweddglo
diff --git a/l10n-cy/toolkit/chrome/mozapps/downloads/downloads.properties b/l10n-cy/toolkit/chrome/mozapps/downloads/downloads.properties
new file mode 100644
index 0000000000..3adc0bd28f
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/mozapps/downloads/downloads.properties
@@ -0,0 +1,115 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# LOCALIZATION NOTE (shortSeconds): Semi-colon list of plural
+# forms. See: http://developer.mozilla.org/en/docs/Localization_and_Plurals
+# s is the short form for seconds
+shortSeconds=e;e;e;e;e;e
+
+# LOCALIZATION NOTE (shortMinutes): Semi-colon list of plural
+# forms. See: http://developer.mozilla.org/en/docs/Localization_and_Plurals
+# m is the short form for minutes
+shortMinutes=m;m;m;m;m;m
+
+# LOCALIZATION NOTE (shortHours): Semi-colon list of plural
+# forms. See: http://developer.mozilla.org/en/docs/Localization_and_Plurals
+# h is the short form for hours
+shortHours=a;a;a;a;a;a
+
+# LOCALIZATION NOTE (shortDays): Semi-colon list of plural
+# forms. See: http://developer.mozilla.org/en/docs/Localization_and_Plurals
+# d is the short form for days
+shortDays=d;d;d;d;d;d
+
+downloadErrorAlertTitle=Gwall llwytho i lawr
+# LOCALIZATION NOTE (downloadErrorBlockedBy): %S is the name of the blocking
+# extension.
+downloadErrorBlockedBy=Nid oes modd cadw'r llwyth am ei fod wedi'i rwystro gan %S.
+# LOCALIZATION NOTE (downloadErrorExtension): used when the blocking extension
+# name is unavailable.
+downloadErrorExtension=Nid oes modd cadw'r llwyth am ei fod wedi'i rwystro gan estyniad.
+downloadErrorGeneric=Nid oes modd cadw'r llwyth yma gan fod gwall anhysbys wedi digwydd.\n\nCeisiwch eto.
+
+# LOCALIZATION NOTE: we don't have proper plural support in the CPP code; bug 463102
+quitCancelDownloadsAlertTitle=Diddymu Pob Llwyth?
+quitCancelDownloadsAlertMsg=Os fyddwch yn gadael, bydd 1 llwyth yn cael ei ddiddymu. Ydych chi'n siŵr eich bod am adael?
+quitCancelDownloadsAlertMsgMultiple=Os fyddwch yn gadael, bydd %S llwyth yn cael eu diddymu. Ydych chi'n siŵr eich bod am adael?
+quitCancelDownloadsAlertMsgMac=Os fyddwch yn gadael, bydd 1 llwyth yn cael ei ddiddymu. Ydych chi'n siŵr eich bod am adael?
+quitCancelDownloadsAlertMsgMacMultiple=Os fyddwch yn gadael, bydd %S llwyth yn cael eu diddymu. Ydych chi'n siŵr eich bod am adael?
+offlineCancelDownloadsAlertTitle=Diddymu Pob Llwyth?
+offlineCancelDownloadsAlertMsg=Os fyddwch yn mynd all-lein, bydd 1 llwyth yn cael ei ddiddymu. Ydych chi'n siŵr eich bod am fynd all-lein?
+offlineCancelDownloadsAlertMsgMultiple=Os fyddwch yn mynd all-lein, bydd %S llwyth yn cael eu diddymu. Ydych chi'n siŵr eich bod am fynd all-lein?
+leavePrivateBrowsingCancelDownloadsAlertTitle=Diddymu Pob Llwyth?
+leavePrivateBrowsingWindowsCancelDownloadsAlertMsg2=Os ydych yn cau pob ffenestr Pori Preifat nawr, bydd 1 llwyth yn cael ei ddiddymu. Ydych chi'n siŵr eich bod am adael y modd Pori Preifat?
+leavePrivateBrowsingWindowsCancelDownloadsAlertMsgMultiple2=Os ydych yn cau pob ffenestr Pori Preifat nawr, bydd %S llwyth yn cael eu diddymu. Ydych chi'n siŵr eich bod am adael y modd Pori Preifat?
+cancelDownloadsOKText=Diddymu 1 Llwyth
+cancelDownloadsOKTextMultiple=Diddymu %S Llwyth
+dontQuitButtonWin=Peidio Gadael
+dontQuitButtonMac=Peidio Gorffen
+dontGoOfflineButton=Aros Ar-lein
+dontLeavePrivateBrowsingButton2=Aros yn y Modd Pori Preifat
+
+# LOCALIZATION NOTE (infiniteRate):
+# If download speed is a JavaScript Infinity value, this phrase is used
+infiniteRate=Cyflym iawn
+
+# LOCALIZATION NOTE (statusFormat3): — is the "em dash" (long dash)
+# %1$S transfer progress; %2$S rate number; %3$S rate unit; %4$S time left
+# example: 4 minutes left — 1.1 of 11.1 GB (2.2 MB/sec)
+statusFormat3=%4$S — %1$S (%2$S %3$S/sec)
+
+# LOCALIZATION NOTE (statusFormatInfiniteRate): — is the "em dash" (long dash)
+# %1$S transfer progress; %2$S substitute phrase for Infinity speed; %3$S time left
+# example: 4 minutes left — 1.1 of 11.1 GB (Really fast)
+statusFormatInfiniteRate=%3$S — %1$S (%2$S)
+
+# LOCALIZATION NOTE (statusFormatNoRate): — is the "em dash" (long dash)
+# %1$S transfer progress; %2$S time left
+# example: 4 minutes left — 1.1 of 11.1 GB
+statusFormatNoRate=%2$S — %1$S
+
+bytes=beit
+kilobyte=KB
+megabyte=MB
+gigabyte=GB
+
+# LOCALIZATION NOTE (transferSameUnits2):
+# %1$S progress number; %2$S total number; %3$S total unit
+# example: 1.1 of 333 MB
+transferSameUnits2=%1$S o %2$S %3$S
+# LOCALIZATION NOTE (transferDiffUnits2):
+# %1$S progress number; %2$S progress unit; %3$S total number; %4$S total unit
+# example: 11.1 MB of 3.3 GB
+transferDiffUnits2=%1$S %2$S o %3$S %4$S
+# LOCALIZATION NOTE (transferNoTotal2):
+# %1$S progress number; %2$S unit
+# example: 111 KB
+transferNoTotal2=%1$S %2$S
+
+# LOCALIZATION NOTE (timePair3): %1$S time number; %2$S time unit
+# example: 1m; 11h
+timePair3=%1$S %2$S
+# LOCALIZATION NOTE (timeLeftSingle3): %1$S time left
+# example: 1m left; 11h left
+timeLeftSingle3=%1$S ar ôl
+# LOCALIZATION NOTE (timeLeftDouble3): %1$S time left; %2$S time left sub units
+# example: 11h 2m left; 1d 22h left
+timeLeftDouble3=%1$S %2$S ar ôl
+timeFewSeconds2=Ychydig eiliadau ar ôl
+timeUnknown2=Amser anhysbys ar ôl
+
+# LOCALIZATION NOTE (doneScheme2): #1 URI scheme like data: jar: about:
+doneScheme2=Adnodd %1$S
+# LOCALIZATION NOTE (doneFileScheme): Special case of doneScheme for file:
+# This is used as an eTLD replacement for local files, so make it lower case
+doneFileScheme=ffeil leol
+
+# LOCALIZATION NOTE (yesterday): Displayed time for files finished yesterday
+yesterday=Ddoe
+
+fileExecutableSecurityWarning=Mae "%S" yn ffeil weithredadwy. Gall ffeiliau gweithredadwy gynnwys firysau neu god maleisus arall gall ddifrodi eich cyfrifiadur. Byddwch ofalus wrth agor y ffeil. Ydych chi'n siŵr eich bod am agor "%S"?
+fileExecutableSecurityWarningTitle=Agor Ffeil Gweithredadwy?
+
+# Desktop folder name for downloaded files
+downloadsFolder=Llwythi
diff --git a/l10n-cy/toolkit/chrome/mozapps/downloads/settingsChange.dtd b/l10n-cy/toolkit/chrome/mozapps/downloads/settingsChange.dtd
new file mode 100644
index 0000000000..ecaa4961ae
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/mozapps/downloads/settingsChange.dtd
@@ -0,0 +1,6 @@
+<!-- This Source Code Form is subject to the terms of the Mozilla Public
+   - License, v. 2.0. If a copy of the MPL was not distributed with this
+   - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
+
+<!ENTITY  settingsChangePreferences.label  "Mae modd newid gosodiadau yn Dewisiadau &brandShortName;.">
+<!ENTITY  settingsChangeOptions.label      "Mae modd newid gosodiadau yn Newisiadau &brandShortName;.">
diff --git a/l10n-cy/toolkit/chrome/mozapps/downloads/unknownContentType.dtd b/l10n-cy/toolkit/chrome/mozapps/downloads/unknownContentType.dtd
new file mode 100644
index 0000000000..9e18d3a09f
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/mozapps/downloads/unknownContentType.dtd
@@ -0,0 +1,26 @@
+<!-- This Source Code Form is subject to the terms of the Mozilla Public
+   - License, v. 2.0. If a copy of the MPL was not distributed with this
+   - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
+
+<!ENTITY  intro2.label                "Rydych wedi dewis agor:">
+<!ENTITY  from.label                  "oddi wrth:">
+<!ENTITY  actionQuestion.label        "Beth ddylai &brandShortName; wneud gyda'r ffeil?">
+
+<!ENTITY  openWith.label              "Agor gyda">
+<!ENTITY  openWith.accesskey          "o">
+<!ENTITY  other.label                 "Arall…">
+
+<!ENTITY  saveFile.label              "Cadw Ffeil">
+<!ENTITY  saveFile.accesskey          "C">
+
+<!ENTITY  rememberChoice.label        "Gwneud hyn yn awtomatig ar gyfer ffeiliau o'r math yma o hyn ymlaen.">
+<!ENTITY  rememberChoice.accesskey    "a">
+
+<!ENTITY  whichIs.label              "sydd yn:">
+
+<!ENTITY  chooseHandlerMac.label      "Dewis…">
+<!ENTITY  chooseHandlerMac.accesskey  "D">
+<!ENTITY  chooseHandler.label         "Pori…">
+<!ENTITY  chooseHandler.accesskey     "P">
+
+<!ENTITY  unknownPromptText.label     "Hoffech chi gadw'r ffeil?">
diff --git a/l10n-cy/toolkit/chrome/mozapps/downloads/unknownContentType.properties b/l10n-cy/toolkit/chrome/mozapps/downloads/unknownContentType.properties
new file mode 100644
index 0000000000..5ecedcca6d
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/mozapps/downloads/unknownContentType.properties
@@ -0,0 +1,24 @@
+# -*- Mode: Java; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+title=Yn agor %S
+saveDialogTitle=Rhowch enw'r ffeil i'w cadw iddi…
+defaultApp=%S (rhagosodiad)
+chooseAppFilePickerTitle=Dewis Rhaglen Cymorth
+badApp=Methu canfod y rhaglen ("%S") rydych wedi ei dewis.  Gwiriwch enw'r ffeil neu ddewis raglen arall.
+badApp.title=Methu canfod y rhaglen
+badPermissions=Nid oedd modd cadw'r ffeil am nad oedd gennych ganiatad i wneud hynny.  Dewiswch gyfeiriadur cadw arall.
+badPermissions.title=Caniatâd Cadw Annilys
+unknownAccept.label=Cadw Ffeil
+unknownCancel.label=Diddymu
+fileType=Ffeil %S
+# LOCALIZATION NOTE (orderedFileSizeWithType): first %S is type, second %S is size, and third %S is unit
+orderedFileSizeWithType=%1$S (%2$S %3$S)
+pdfHandlerDescription=Fformat Dogfen Gludadwy
+avifExtHandlerDescription=Ffeil Delwedd AV1 (AVIF)
+pdfExtHandlerDescription=Portable Document Format (PDF)
+svgExtHandlerDescription=Scalable Vector Graphics (SVG)
+webpExtHandlerDescription=Delwedd WebP
+xmlExtHandlerDescription=Extensible Markup Language (XML)
diff --git a/l10n-cy/toolkit/chrome/mozapps/extensions/extensions.dtd b/l10n-cy/toolkit/chrome/mozapps/extensions/extensions.dtd
new file mode 100644
index 0000000000..42c0ab2297
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/mozapps/extensions/extensions.dtd
@@ -0,0 +1,5 @@
+<!-- This Source Code Form is subject to the terms of the Mozilla Public
+   - License, v. 2.0. If a copy of the MPL was not distributed with this
+   - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
+
+<!ENTITY setting.learnmore "Dysgu Rhagor…">
diff --git a/l10n-cy/toolkit/chrome/mozapps/extensions/extensions.properties b/l10n-cy/toolkit/chrome/mozapps/extensions/extensions.properties
new file mode 100644
index 0000000000..3d034f5bfd
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/mozapps/extensions/extensions.properties
@@ -0,0 +1,84 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+#LOCALIZATION NOTE (notification.incompatible) %1$S is the add-on name, %2$S is brand name, %3$S is application version
+notification.incompatible=Mae %1$S yn anghydnaws â %2$S %3$S.
+#LOCALIZATION NOTE (notification.unsigned, notification.unsignedAndDisabled) %1$S is the add-on name, %2$S is brand name
+notification.unsignedAndDisabled=Nid oedd modd dilysu %1$S i'w ddefnyddio yn %2$S ac mae wedi ei analluogi.
+notification.unsigned=Nid oedd modd dilysu %1$S i'w defnyddio yn %2$S. Cymerwch ofal.
+notification.unsigned.link=Rhagor o Wybodaeth
+#LOCALIZATION NOTE (notification.blocked) %1$S is the add-on name
+notification.blocked=Mae %1$S wedi ei analluogi o ganlyniad i faterion diogelwch a sefydlogrwydd.
+notification.blocked.link=Rhagor o Wybodaeth
+#LOCALIZATION NOTE (notification.softblocked) %1$S is the add-on name
+notification.softblocked=Mae'n hysbys fod %1$S yn achosi anawsterau diogelwch a sefydlogrwydd.
+notification.softblocked.link=Rhagor o Wybodaeth
+#LOCALIZATION NOTE (notification.outdated) %1$S is the add-on name
+notification.outdated=Mae diweddariad pwysig ar gael ar gyfer %1$S.
+notification.outdated.link=Diweddaru Nawr
+#LOCALIZATION NOTE (notification.vulnerableUpdatable) %1$S is the add-on name
+notification.vulnerableUpdatable=Mae'n hysbys fod %1$S yn fregus a dylai gael ei ddiweddaru.
+notification.vulnerableUpdatable.link=Diweddaru Nawr
+#LOCALIZATION NOTE (notification.vulnerableNoUpdate) %1$S is the add-on name
+notification.vulnerableNoUpdate=Mae'n hysbys fod %1$S yn fregus. Defnyddiwch gyda gofal.
+notification.vulnerableNoUpdate.link=Rhagor o Wybodaeth
+#LOCALIZATION NOTE (notification.restartless-uninstall) %1$S is the add-on name
+notification.restartless-uninstall=Bydd %1$S yn cael ei ddadosod ar ôl i chi gau'r tab.
+#LOCALIZATION NOTE (notification.downloadError) %1$S is the add-on name.
+notification.downloadError=Bu gwall wrth lwytho %1$S i lawr.
+notification.downloadError.retry=Ceisio eto
+notification.downloadError.retry.tooltip=Ceisiwch lwytho'r ychwanegyn eto
+#LOCALIZATION NOTE (notification.installError) %1$S is the add-on name.
+notification.installError=Bu gwall wrth osod %1$S.
+notification.installError.retry=Ceisio eto
+notification.installError.retry.tooltip=Ceisiwch lwytho i lawr a gosod yr ychwanegyn yma eto
+#LOCALIZATION NOTE (notification.gmpPending) %1$S is the add-on name.
+notification.gmpPending=Bydd %1$S yn cael ei osod yn fuan.
+
+#LOCALIZATION NOTE (details.notification.incompatible) %1$S is the add-on name, %2$S is brand name, %3$S is application version
+details.notification.incompatible=Mae %1$S yn anghydnaws â %2$S %3$S.
+#LOCALIZATION NOTE (details.notification.unsigned, details.notification.unsignedAndDisabled) %1$S is the add-on name, %2$S is brand name
+details.notification.unsignedAndDisabled=Nid oedd modd dilysu %1$S i'w ddefnyddio yn %2$S ac mae wedi ei analluogi.
+details.notification.unsigned=Nid oedd modd dilysu %1$S i'w defnyddio yn %2$S. Cymerwch ofal.
+details.notification.unsigned.link=Rhagor o Wybodaeth
+#LOCALIZATION NOTE (details.notification.blocked) %1$S is the add-on name
+details.notification.blocked=Mae %1$S wedi ei analluogi o ganlyniad i faterion diogelwch a sefydlogrwydd.
+details.notification.blocked.link=Rhagor o Wybodaeth
+#LOCALIZATION NOTE (details.notification.softblocked) %1$S is the add-on name
+details.notification.softblocked=Mae'n hysbys fod %1$S yn achosi anawsterau diogelwch a sefydlogrwydd.
+details.notification.softblocked.link=Rhagor o Wybodaeth
+#LOCALIZATION NOTE (details.notification.outdated) %1$S is the add-on name
+details.notification.outdated=Mae diweddariad pwysig ar gael ar gyfer %1$S.
+details.notification.outdated.link=Diweddaru Nawr
+#LOCALIZATION NOTE (details.notification.vulnerableUpdatable) %1$S is the add-on name
+details.notification.vulnerableUpdatable=Mae'n hysbys fod %1$S yn fregus a dylai gael ei ddiweddaru.
+details.notification.vulnerableUpdatable.link=Diweddaru Nawr
+#LOCALIZATION NOTE (details.notification.vulnerableNoUpdate) %1$S is the add-on name
+details.notification.vulnerableNoUpdate=Mae'n hysbys fod %1$S yn fregus. Defnyddiwch gyda gofal.
+details.notification.vulnerableNoUpdate.link=Rhagor o Wybodaeth
+#LOCALIZATION NOTE (details.notification.restartless-uninstall) %1$S is the add-on name.
+details.notification.restartless-uninstall=Bydd %1$S yn cael ei ddadosod ar ôl i chi gau'r tab.
+#LOCALIZATION NOTE (details.notification.gmpPending) %1$S is the add-on name
+details.notification.gmpPending=Bydd %1$S yn cael ei osod yn fuan.
+
+type.extension.name=Estyniadau
+type.themes.name=Themâu
+type.locale.name=Iaith
+type.plugin.name=Ategion
+type.dictionary.name=Geiriaduron
+type.service.name=Gwasanaethau
+type.legacy.name=Hen Estyniadau
+type.unsupported.name=Heb eu Cynnal
+
+#LOCALIZATION NOTE(listHeading.discover) %S is the brandShortName
+listHeading.discover=Personoli Eich %S
+listHeading.extension=Rheoli eich estyniadau
+listHeading.shortcuts=Rheoli Estyniad Llwybrau Byr
+listHeading.theme=Rheoli eich themâu
+listHeading.plugin=Rheoli eich ategion
+listHeading.locale=Rheoli eich ieithoedd
+listHeading.dictionary=Rheoli eich geiriaduron
+
+searchLabel.extension=Canfod estyniadau eraill
+searchLabel.theme=Canfod themâu eraill
diff --git a/l10n-cy/toolkit/chrome/mozapps/handling/handling.dtd b/l10n-cy/toolkit/chrome/mozapps/handling/handling.dtd
new file mode 100644
index 0000000000..b250ba8c3c
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/mozapps/handling/handling.dtd
@@ -0,0 +1,10 @@
+<!-- This Source Code Form is subject to the terms of the Mozilla Public
+   - License, v. 2.0. If a copy of the MPL was not distributed with this
+   - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
+
+<!ENTITY window.emWidth "26em">
+<!ENTITY window.emHeight "26em">
+<!ENTITY ChooseOtherApp.description "Dewis Rhaglen arall">
+<!ENTITY ChooseApp.label "Dewis…">
+<!ENTITY ChooseApp.accessKey "D">
+<!ENTITY accept "Agor dolen">
diff --git a/l10n-cy/toolkit/chrome/mozapps/handling/handling.properties b/l10n-cy/toolkit/chrome/mozapps/handling/handling.properties
new file mode 100644
index 0000000000..b215fc17a2
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/mozapps/handling/handling.properties
@@ -0,0 +1,15 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+protocol.title=Cychwyn y Rhaglen
+protocol.description=Mae angen agor y ddolen gyda rhaglen.
+protocol.choices.label=Anfon at:
+protocol.checkbox.label=Cofio fy newis ar gyfer dolenni %S.
+protocol.checkbox.accesskey=C
+protocol.checkbox.extra=Gall hyn gael ei newid yn Newisiadau %S.
+
+# Displayed under the name of a protocol handler in the Launch Application dialog.
+privatebrowsing.disabled.label=Analluogwyd mewn Ffenestri Preifat
+
+choose.application.title=Rhaglen Arall…
diff --git a/l10n-cy/toolkit/chrome/mozapps/profile/profileSelection.properties b/l10n-cy/toolkit/chrome/mozapps/profile/profileSelection.properties
new file mode 100644
index 0000000000..5f8e18446b
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/mozapps/profile/profileSelection.properties
@@ -0,0 +1,57 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# LOCALIZATION NOTE: These strings are used for startup/profile problems and the profile manager.
+
+# Application not responding
+# LOCALIZATION NOTE (restartTitle, restartMessageNoUnlocker2, restartMessageUnlocker, restartMessageNoUnlockerMac, restartMessageUnlockerMac): Messages displayed when the application is running but is not responding to commands. %S is the application name.
+restartTitle=Cau %S
+restartMessageNoUnlocker2=Mae %S eisoes yn rhedeg, ond nid yw'n ymateb. I ddefnyddio %S, yn gyntaf rhaid i chi gau'r broses %S bresennol, ailgychwynnwch eich dyfais, neu ddefnyddio proffil gwahanol.
+restartMessageUnlocker=Mae %S yn rhedeg ond nid yw'n ymateb. Rhaid cau'r hen broses %S cyn agor ffenestr newydd.
+restartMessageNoUnlockerMac=Mae copi o %S eisoes ar agor. Dim ond un copi o %S gall fod ar agor ar unrhyw adeg.
+restartMessageUnlockerMac=Mae copi o %S eisoes ar agor. Bydd y copi o %S sy'n rhedeg yn cau er mwyn agor hon.
+
+# Profile manager
+# LOCALIZATION NOTE (profileTooltip): First %S is the profile name, second %S is the path to the profile folder.
+profileTooltip=Proffil: '%S' - Llwybr: '%S'
+
+pleaseSelectTitle=Dewis Proffil
+pleaseSelect=Dewiswch broffil i gychwyn %S, neu greu proffil newydd.
+
+renameProfileTitle=Newid Enw Proffil
+renameProfilePrompt=Ailenwi'r proffil "%S" i:
+
+profileNameInvalidTitle=Enw proffil annilys
+profileNameInvalid=Methu caniatáu enw proffil "%S".
+
+chooseFolder=Dewiswch Ffolder Proffil
+profileNameEmpty=Methu derbyn enw proffil gwag.
+invalidChar=Methu cynnwys nod "%S" mewn enw proffil. Dewiswch enw arall.
+
+deleteTitle=Dileu Proffil
+deleteProfileConfirm=Bydd dileu proffil yn tynnu'r proffil o'r rhestr o broffiliau sydd ar gael ac nid oes modd ei ddadwneud.\nGallwch hefyd ddewis i ddileu ffeiliau data proffil, gan gynnwys eich gosodiadau, tystysgrifau a data arall yn perthyn i ddefnyddwyr. Bydd y dewis hwn yn dileu ffolder "%S" ac nid oes modd ei ddadwneud.\nHoffech chi ddileu'r ffeiliau data proffil?
+deleteFiles=Dileu Ffeiliau
+dontDeleteFiles=Peidio Dileu Ffeiliau
+
+profileCreationFailed=Methu creu proffil. Mwy na thebyg mae'r ffolder yn anysgrifenadwy.
+profileCreationFailedTitle=Methodd creu Proffil
+profileExists=Mae proffil gyda'r enw eisoes yn bod. Dewiswch enw arall.
+profileFinishText=Cliciwch Gorffen i greu'r proffil newydd.
+profileFinishTextMac=Cliciwch Gorffen i greu'r proffil newydd.
+profileMissing=Methu llwytho eich proffil %S. Gall fod ar goll neu anhygyrch.
+profileMissingTitle=Proffil ar Goll
+profileDeletionFailed=Nid oedd modd dileu'r proffil gan efallai ei fod yn cael ei ddefnyddio.
+profileDeletionFailedTitle=Methodd y Dileu
+
+# Profile reset
+# LOCALIZATION NOTE (resetBackupDirectory): Directory name for the profile directory backup created during reset. This directory is placed in a location users will see it (ie. their desktop). %S is the application name.
+resetBackupDirectory=Hen Ddata %S
+
+flushFailTitle=Heb gadw'r newidiadau
+# LOCALIZATION NOTE (conflictMessage): %1$S is brandProductName, %2$S is brandShortName.
+conflictMessage=Mae copi arall o %1$S wedi gwneud newidiadau i broffiliau. Rhaid ailgychwyn %2$S cyn gwneud mwy o newidiadau.
+flushFailMessage=Mae gwall annisgwyl wedi atal eich newidiadau rhag cael eu cadw.
+# LOCALIZATION NOTE (flushFailRestartButton): $S is brandShortName.
+flushFailRestartButton=Ailgychwyn %S
+flushFailExitButton=Gadael
diff --git a/l10n-cy/toolkit/chrome/mozapps/update/updates.properties b/l10n-cy/toolkit/chrome/mozapps/update/updates.properties
new file mode 100644
index 0000000000..4e5d49997b
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/mozapps/update/updates.properties
@@ -0,0 +1,45 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# LOCALIZATION NOTE: The 1st %S is brandShortName and 2nd %S is update version
+# where update version from the update xml
+# example: MyApplication 10.0.5
+updateName=%S %S
+
+noThanksButton=Dim Diolch
+noThanksButton.accesskey=i
+# NOTE: The restartLaterButton string is also used in
+# mozapps/extensions/content/blocklist.js
+restartLaterButton=Ailgychwyn Rhywbryd Eto
+restartLaterButton.accesskey=l
+restartNowButton=Ailgychwyn %S
+restartNowButton.accesskey=i
+
+statusFailed=Methodd y Gosod
+
+installSuccess=Cafodd y Diweddariad ei osod yn llwyddiannus
+installPending=Gosod yn Disgwyl
+patchApplyFailure=Methu gosod y Diweddariad (methodd gosod y darn)
+elevationFailure=Nid oes gennych y caniatâd angenrheidiol i osod y diweddariad. Cysylltwch â' ch gweinyddwr system.
+
+check_error-200=Ffeil XML diweddaru wedi ei gam-ffurfio (200)
+check_error-403=Gwrthod mynediad (403)
+check_error-404=Heb ganfod Ffeil Diweddaru XML (404)
+check_error-500=Gwall gweinydd mewnol (500)
+check_error-2152398849=Methwyd (rheswm anhysbys)
+check_error-2152398861=Gwrthodwyd cysylltiad
+check_error-2152398862=Cysylltiad wedi dod i ben
+# NS_ERROR_OFFLINE
+check_error-2152398864=Rhwydwaith all-lein (ewch ar-lein)
+check_error-2152398867=Gwrthod pyrth
+check_error-2152398868=Heb dderbyn data (ceisiwch eto)
+check_error-2152398878=Heb ganfod diweddariad gweinydd (gwirio'r cyswllt i'r we)
+check_error-2152398890=Heb ganfod gweinydd dirprwy (gwirio'r cyswllt i'r we)
+# NS_ERROR_DOCUMENT_NOT_CACHED
+check_error-2152398918=Rhwydwaith all-lein (ewch ar-lein)
+check_error-2152398919=Torrwyd ar drosglwyddiad data (ceisiwch eto)
+check_error-2152398920=Gwrthodwyd cysylltiad â'r gweinydd dirprwy
+check_error-2153390069=Mae tystysgrif y gweinydd wedi dod i ben (newidiwch gloc eich system i'r dyddiad a'r amser cywir os yw'n anghywir)
+check_error-verification_failed=Nid oedd modd dilysu cywirdeb y diweddariad
+check_error-move_failed=Wedi methu paratoi'r diweddariad i'w osod
diff --git a/l10n-cy/toolkit/chrome/passwordmgr/passwordmgr.properties b/l10n-cy/toolkit/chrome/passwordmgr/passwordmgr.properties
new file mode 100644
index 0000000000..f5572bf254
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/passwordmgr/passwordmgr.properties
@@ -0,0 +1,74 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+rememberPassword = Defnyddio'r Rheolwr Cyfrinair i gofio'r cyfrinair.
+savePasswordTitle = Cadarnhau
+# LOCALIZATION NOTE (saveLoginMsg, saveLoginMsgNoUser):
+# %1$S is brandShortName, %2$S is the login's hostname.
+saveLoginMsg = Hoffech chi i %1$S gadw'r mewngofnodiad hwn ar gyfer %2$S?
+saveLoginMsgNoUser = Hoffech chi i %1$S gadw'r cyfrinair hwn ar gyfer %2$S?
+saveLoginButtonAllow.label = Cadw
+saveLoginButtonAllow.accesskey = C
+saveLoginButtonDeny.label = Peidio â Chadw
+saveLoginButtonDeny.accesskey = P
+saveLoginButtonNever.label = Peidio Byth â Chadw
+saveLoginButtonNever.accesskey = P
+updateLoginMsg = Hoffech chi ddiweddaru'r mewngofnod?
+updateLoginMsgNoUser = Hoffech chi ddiweddaru'r cyfrinair?
+updateLoginMsgAddUsername = Hoffech chi ychwanegu enw defnyddiwr at y cyfrinair a gadwyd?
+updateLoginButtonText = Diweddaru
+updateLoginButtonAccessKey = i
+updateLoginButtonDeny.label = Peidio â Diweddaru
+updateLoginButtonDeny.accesskey = P
+updateLoginButtonDelete.label = Tynnu Mewngofnod wedi'i Gadw
+updateLoginButtonDelete.accesskey = T
+# LOCALIZATION NOTE (rememberPasswordMsg):
+# 1st string is the username for the login, 2nd is the login's hostname.
+# Note that long usernames may be truncated.
+rememberPasswordMsg = Hoffech chi gofio cyfrinair ar gyfer "%1$S" ar %2$S?
+# LOCALIZATION NOTE (rememberPasswordMsgNoUsername):
+# String is the login's hostname.
+rememberPasswordMsgNoUsername = Hoffech chi gofio'r cyfrinair ar %S?
+# LOCALIZATION NOTE (noUsernamePlaceholder):
+# This is displayed in place of the username when it is missing.
+noUsernamePlaceholder=Dim enw defnyddiwr
+togglePasswordLabel=Dangos cyfrineiriau
+togglePasswordAccessKey2=d
+notNowButtonText = &Nid Nawr
+neverForSiteButtonText = &Byth ar Gyfer y Wefan yma
+rememberButtonText = &Cofio
+passwordChangeTitle = Cadarnhau Newid Cyfrinair
+# LOCALIZATION NOTE (updatePasswordMsg):
+# String is the username for the login.
+updatePasswordMsg = Hoffech chi ddiweddaru cyfrinair "%S"?
+updatePasswordMsgNoUser = Hoffech chi ddiweddaru'r cyfrinair?
+userSelectText2 = Dewis pa fewngofnod i'w ddiweddaru:
+loginsDescriptionAll2=Mae'r cyfrineiriau ar gyfer y gwefannau hyn ar gadw ar eich cyfrifiadur
+
+# LOCALIZATION NOTE (useASecurelyGeneratedPassword):
+# Shown in the autocomplete popup to allow filling a generated password into a password field.
+useASecurelyGeneratedPassword=Defnyddiwch Gyfrinair sydd wedi ei Gynhyrchu'n Ddiogel
+# LOCALIZATION NOTE (generatedPasswordWillBeSaved):
+# %S will contain the brandShorterName. This informs the user that the generated password will be automatically saved.
+generatedPasswordWillBeSaved=Bydd %S yn cadw'r cyfrinair hwn ar gyfer y wefan hon.
+# LOCALIZATION NOTE (loginHostAge):
+# This is used to show the context menu login items with their age.
+# 1st string is the username for the login, 2nd is the login's age.
+loginHostAge=%1$S (%2$S)
+# LOCALIZATION NOTE (noUsername):
+# String is used on the context menu when a login doesn't have a username.
+noUsername=Dim enw defnyddiwr
+
+# LOCALIZATION NOTE (displaySameOrigin):
+# String is used on the autocomplete row when the login origin is a domain match with the document origin
+displaySameOrigin=O'r wefan hon
+
+# LOCALIZATION NOTE (insecureFieldWarningDescription2):
+# %1$S will contain insecureFieldWarningLearnMore and look like a link to indicate that clicking will open a tab with support information.
+insecureFieldWarningDescription2 = Nid yw'r cysylltiad yn ddiogel. Gall fewngofnodion sydd wedi eu rhoi yma gael eu cyfaddawdu. %1$S
+insecureFieldWarningLearnMore = Dysgu Rhagor
+
+# LOCALIZATION NOTE (viewSavedLogins.label):
+# This label is used in the footer of login autocomplete menus.
+viewSavedLogins.label= Gweld Mewngofnodion wedi eu Cadw
diff --git a/l10n-cy/toolkit/chrome/places/places.properties b/l10n-cy/toolkit/chrome/places/places.properties
new file mode 100644
index 0000000000..d45a16db4e
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/places/places.properties
@@ -0,0 +1,33 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+BookmarksMenuFolderTitle=Dewislen Nodau Tudalen
+BookmarksToolbarFolderTitle=Bar Offer Nodau Tudalen
+OtherBookmarksFolderTitle=Nodau Tudalen Eraill
+TagsFolderTitle=Tagiau
+MobileBookmarksFolderTitle=Nodau Tudalen Symudol
+
+OrganizerQueryHistory=Hanes
+OrganizerQueryDownloads=Llwythi
+OrganizerQueryAllBookmarks=Pob Nod Tudalen
+
+# LOCALIZATION NOTE (dateName):
+# These are used to generate history containers when history is grouped by date
+finduri-AgeInDays-is-0=Heddiw
+finduri-AgeInDays-is-1=Ddoe
+finduri-AgeInDays-is=%S diwrnod yn ôl
+finduri-AgeInDays-last-is=Y %S diwrnod diwethaf
+finduri-AgeInDays-isgreater=Hŷn na %S diwrnod
+finduri-AgeInMonths-is-0=Y mis yma
+finduri-AgeInMonths-isgreater=Hŷn na %S mis
+
+# LOCALIZATION NOTE (localFiles):
+# This is used to generate local files container when history is grouped by site
+localhost=(ffeiliau lleol)
+
+# LOCALIZATION NOTE
+# The string is used for showing file size of each backup in the "fileRestorePopup" popup
+# %1$S is the file size
+# %2$S is the file size unit
+backupFileSizeText=%1$S %2$S
diff --git a/l10n-cy/toolkit/chrome/pluginproblem/pluginproblem.dtd b/l10n-cy/toolkit/chrome/pluginproblem/pluginproblem.dtd
new file mode 100644
index 0000000000..b4e2581aaf
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/pluginproblem/pluginproblem.dtd
@@ -0,0 +1,33 @@
+<!-- This Source Code Form is subject to the terms of the Mozilla Public
+   - License, v. 2.0. If a copy of the MPL was not distributed with this
+   - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
+<!-- LOCALIZATION NOTE (tapToPlayPlugin): Mobile (used for touch interfaces) only has one type of plugin possible. -->
+
+<!ENTITY tapToPlayPlugin                                     "Cliciwch yma i gychwyn yr ategyn.">
+<!ENTITY clickToActivatePlugin                               "Gweithredu'r ategyn.">
+<!ENTITY checkForUpdates                                     "Gwirio am ddiweddariadau…">
+<!ENTITY blockedPlugin.label                                 "Mae'r ategyn wedi ei rwystro er eich diogelwch.">
+<!ENTITY hidePluginBtn.label                                 "Cuddio ategyn">
+<!ENTITY managePlugins                                       "Rheoli ategion…">
+
+<!-- LOCALIZATION NOTE (reloadPlugin.pre): include a trailing space as needed -->
+<!-- LOCALIZATION NOTE (reloadPlugin.middle): avoid leading/trailing spaces, this text is a link -->
+<!-- LOCALIZATION NOTE (reloadPlugin.post): include a starting space as needed -->
+
+<!ENTITY reloadPlugin.pre                                    "">
+<!ENTITY reloadPlugin.middle                                 "Ail lwytho'r dudalen">
+<!ENTITY reloadPlugin.post                                   " i geisio eto.">
+<!-- LOCALIZATION NOTE (report.please): This and the other report.* strings should be as short as possible, ideally 2-3 words. -->
+<!ENTITY report.please                                       "Anfon adroddiad chwalu">
+<!ENTITY report.submitting                                   "Anfon yr adroddiad…">
+<!ENTITY report.submitted                                    "Wedi anfon adroddiad chwalu.">
+<!ENTITY report.disabled                                     "Adrodd ar chwalu wedi ei analluogi.">
+<!ENTITY report.failed                                       "Cyflwyno wedi methu.">
+<!ENTITY report.unavailable                                  "Dim adroddiad ar gael.">
+<!ENTITY report.comment                                      "Ychwanegu sylw (sylwadau yn weladwy'n gyhoeddus)">
+<!ENTITY report.pageURL                                      "Cynnwys URL y dudalen">
+
+<!ENTITY plugin.file                                         "Ffeil">
+<!ENTITY plugin.mimeTypes                                    "Math MIME">
+<!ENTITY plugin.flashProtectedMode.label                     "Galluogi modd diogel Adobe Flash">
+<!ENTITY plugin.enableBlocklists.label                       "Rhwystro cynnwys Flash peryglus ac ymwthiol">
diff --git a/l10n-cy/toolkit/chrome/search/search.properties b/l10n-cy/toolkit/chrome/search/search.properties
new file mode 100644
index 0000000000..c40297c1d4
--- /dev/null
+++ b/l10n-cy/toolkit/chrome/search/search.properties
@@ -0,0 +1,19 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+addEngineConfirmTitle=Ychwanegu Peiriant Chwilio
+addEngineConfirmation=Ychwanegu "%S" i'r rhestr o beiriannau chwilio sydd ar gael yn y bar chwilio?\n\nO: %S
+addEngineAsCurrentText=Gwneud hwn y peiriant chwilio c&yfredol
+addEngineAddButtonLabel=Ychwanegu
+
+error_loading_engine_title=Gwall llwytho i lawr
+# LOCALIZATION NOTE (error_loading_engine_msg2): %1$S = brandShortName, %2$S = location
+error_loading_engine_msg2=Methodd %S â llwytho i lawr yr ategyn chwilio o:\n%S
+error_duplicate_engine_msg=Methodd %S â gosod yr ategyn chwilio o "%S" gan fod peiriant chwilio sydd â'r un enw yn bodoli'n barod.
+
+error_invalid_engine_title=Gwall Gosod
+error_invalid_format_title=Fformat Annilys
+# LOCALIZATION NOTE (error_invalid_engine_msg2): %1$S = brandShortName, %2$S = location (url)
+error_invalid_engine_msg2=Nid yw %1$S yn gallu gosod y peiriant chwilio o %2$S
+
diff --git a/l10n-cy/toolkit/crashreporter/aboutcrashes.ftl b/l10n-cy/toolkit/crashreporter/aboutcrashes.ftl
new file mode 100644
index 0000000000..1cc78a899b
--- /dev/null
+++ b/l10n-cy/toolkit/crashreporter/aboutcrashes.ftl
@@ -0,0 +1,31 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v- 2-0- If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla-org/MPL/2-0/-
+
+
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+crash-reports-title = Adroddiadau Chwalu
+
+submit-all-button-label = Cyflwyno Popeth
+delete-button-label = Clirio Popeth
+delete-confirm-title = Ydych chi'n siŵr?
+delete-unsubmitted-description = Bydd hyn yn dileu pob adroddiad chwalu heb eu cyflwyno ac nid oes modd ei ddadwneud.
+delete-submitted-description = Bydd hyn yn dileu'r rhestr o adroddiadau chwalu sydd wedi eu cyflwyno ond ni bydd yn dileu'r data sydd wedi ei gyflwyno. Nid oes modd dadwneud hyn.
+
+crashes-unsubmitted-label = Adroddiadau Chwalu heb eu Cyflwyno
+id-heading = Enw'r Adroddiad
+date-crashed-heading = Dyddiad y Chwalu
+submit-crash-button-label = Cyflwyno
+# This text is used to replace the label of the crash submit button
+# if the crash submission fails.
+submit-crash-button-failure-label = Methiant
+
+crashes-submitted-label = Adroddiadau Chwalu
+date-submitted-heading = Dyddiad Cyflwynwyd
+view-crash-button-label = Golwg
+
+no-reports-label = Does dim adroddiadau chwalu wedi eu cyflwyno.
+no-config-label = Mae'r rhaglen wedi ei ffurfweddu i ddangos adroddiadau chwalu. Rhaid gosod y <code>breakpad.reportURL</code>.
diff --git a/l10n-cy/toolkit/crashreporter/crashreporter.ini b/l10n-cy/toolkit/crashreporter/crashreporter.ini
new file mode 100644
index 0000000000..eafedbbd4d
--- /dev/null
+++ b/l10n-cy/toolkit/crashreporter/crashreporter.ini
@@ -0,0 +1,60 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# This file is in the UTF-8 encoding
+[Strings]
+# LOCALIZATION NOTE (isRTL):
+# Leave this entry empty unless your language requires right-to-left layout,
+# for example like Arabic, Hebrew, Persian. If your language needs RTL, please
+# use the untranslated English word "yes" as value
+isRTL=
+CrashReporterTitle=Adroddwr Chwalu
+# LOCALIZATION NOTE (CrashReporterVendorTitle): %s is replaced with the vendor name.  (i.e. "Mozilla")
+CrashReporterVendorTitle=Adroddwr Chwalu %s
+# LOCALIZATION NOTE (CrashReporterErrorText): %s is replaced with another string containing detailed information.
+CrashReporterErrorText=Profodd y rhaglen anhawster ac mae wedi chwalu.\n\nYn anffodus, nid yw'r adroddwr chwalu yn gallu cyflwyno adroddiad am y chwalfa.\n\nManylion: %s
+# LOCALIZATION NOTE (CrashReporterProductErrorText2): The first %s is replaced with the product name (i.e. "Firefox"), the second is replaced with another string containing detailed information.  These two substitutions can not be reordered!
+CrashReporterProductErrorText2=Profodd %s anhawster ac mae wedi chwalu.\n\nYn anffodus, nid yw'r adroddwr chwalu yn medru cyflwyno adroddiad chwalu.\n\nManylion: %s
+CrashReporterSorry=Ymddiheuriadau
+# LOCALIZATION NOTE (CrashReporterDescriptionText2): The %s is replaced with the product name.
+CrashReporterDescriptionText2=Profodd %s anhawster ac mae wedi chwalu.\n\nI'n cynorthwyo i ddatrys yr anhawster, anfonwch adroddiad gwall atom.
+CrashReporterDefault=Mae'r rhaglen yn cael ei rhedeg ar ôl chwalfa er mwyn adrodd ar anhawster i ddarparwr y rhaglen.  Ni ddylai gael ei redeg yn uniongyrchol.
+Details=Manylion…
+ViewReportTitle=Cynnwys yr Adroddiad
+CommentGrayText=Ychwanegu sylw (sylwadau yn weladwy'n gyhoeddus)
+ExtraReportInfo=Mae'r adroddiad hefyd yn cynnwys gwybodaeth dechnegol am gyflwr y rhaglen wrth iddi chwalu.
+# LOCALIZATION NOTE (CheckSendReport): The %s is replaced with the vendor name.
+CheckSendReport=Dweud wrth %s am y chwalfa fel bod modd ei drwsio
+CheckIncludeURL=Cynnwys cyfeiriad y dudalen roeddwn arni
+CheckAllowEmail=Gadael i %s gysylltu â mi am yr adroddiad
+EmailGrayText=Rhowch eich cyfeiriad e-bost yma
+ReportPreSubmit2=Bydd eich adroddiad chwalu yn cael ei gyflwyno cyn i chi adael neu ail gychwyn.
+ReportDuringSubmit2=Cyflwyno eich adroddiad…
+ReportSubmitSuccess=Adroddiad wedi ei gyflwyno'n llwyddiannus!
+ReportSubmitFailed=Bu anhawster wrth gyflwyno eich adroddiad.
+ReportResubmit=Ail anfon adroddiadau fethwyd eu hanfon yn y gorffennol…
+# LOCALIZATION NOTE (Quit2): The %s is replaced with the product name.
+Quit2=Gadael %s
+# LOCALIZATION NOTE (Restart): The %s is replaced with the product name.
+Restart=Ailgychwyn %s
+Ok=Iawn
+Close=Cau
+
+# LOCALIZATION NOTE (CrashID): The %s is replaced with the Crash ID from the server, which is a string like abc12345-6789-0abc-def1-23456abcdef1
+CrashID=Enw Chwalfa: %s
+# LOCALIZATION NOTE (CrashDetailsURL): The %s is replaced with a URL that the user can visit to view the crash details.
+CrashDetailsURL=Mae modd gweld manylion y chwalu yn %s
+ErrorBadArguments=Mae'r rhaglen wedi mynegi ymresymiad annilys.
+ErrorExtraFileExists=Nid yw'r rhaglen wedi gadael ffeil data rhaglen.
+ErrorExtraFileRead=Methu darllen ffeil data'r rhaglen.
+ErrorExtraFileMove=Methu symud ffeil data'r rhaglen.
+ErrorDumpFileExists=Nid yw'r rhaglen wedi gadel ffeil swp chwalu.
+ErrorDumpFileMove=Methu symud swp chwalu.
+ErrorNoProductName=Nid yw'r rhaglen wedi amlygu ei hun.
+ErrorNoServerURL=Nid yw'r rhaglen wedi enwi gweinydd adrodd chwalu.
+ErrorNoSettingsPath=Methu canfod gosodiadau'r adroddwr chwalu.
+ErrorCreateDumpDir=Methu creu cyfeiriadur swp disgwylgar.
+# LOCALIZATION NOTE (ErrorEndOfLife): The %s is replaced with the product name.
+ErrorEndOfLife=Nid yw'r fersiwn o %s rydych yn ei ddefnyddio'n cael ei gynnal bellach. Nid yw adroddiadau chwalu'n cael eu derbyn bellach o'r fersiwn yma. Ystyriwch ddiweddaru i fersiwn sy'n cael ei gynnal.
+
diff --git a/l10n-cy/toolkit/defines.inc b/l10n-cy/toolkit/defines.inc
new file mode 100644
index 0000000000..7121d25835
--- /dev/null
+++ b/l10n-cy/toolkit/defines.inc
@@ -0,0 +1 @@
+#define MOZ_LANG_TITLE Cymraeg
diff --git a/l10n-cy/toolkit/toolkit/about/aboutAbout.ftl b/l10n-cy/toolkit/toolkit/about/aboutAbout.ftl
new file mode 100644
index 0000000000..9c93e1bcd7
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/about/aboutAbout.ftl
@@ -0,0 +1,9 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+about-about-title = About About
+about-about-note =
+    Dyma restr o dudalennau “about” er hwylustod.<br/>
+    Gall rhai ohonynt fod yn ddryslyd. Mae rhai ar gyfer pwrpas canfod gwallau yn unig.<br/>
+    Ac mae rhai ar goll am fod angen llinyn ymholiad arnynt.
diff --git a/l10n-cy/toolkit/toolkit/about/aboutAddons.ftl b/l10n-cy/toolkit/toolkit/about/aboutAddons.ftl
new file mode 100644
index 0000000000..26b6c9bdd2
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/about/aboutAddons.ftl
@@ -0,0 +1,431 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+addons-window =
+    .title = Rheolwr Ychwanegion
+addons-page-title = Rheolwr Ychwanegion
+search-header =
+    .placeholder = Search addons.mozilla.org
+    .searchbuttonlabel = Chwilio
+search-header-shortcut =
+    .key = f
+list-empty-installed =
+    .value = Nid oes gennych ychwanegion o'r math yma wedi eu gosod
+list-empty-available-updates =
+    .value = Heb ganfod diweddariadau
+list-empty-recent-updates =
+    .value = Nid ydych wedi diweddaru eich ychwanegion yn ddiweddar
+list-empty-find-updates =
+    .label = Gwirio am Ddiweddariadau
+list-empty-button =
+    .label = Dysgu rhagor am ychwanegion
+help-button = Cefnogaeth Ychwanegion
+sidebar-help-button-title =
+    .title = Cefnogaeth Ychwanegion
+preferences =
+    { PLATFORM() ->
+        [windows] Dewisiadau { -brand-short-name }
+       *[other] Dewisiadau { -brand-short-name }
+    }
+sidebar-preferences-button-title =
+    .title =
+        { PLATFORM() ->
+            [windows] Dewisiadau { -brand-short-name }
+           *[other] Dewisiadau { -brand-short-name }
+        }
+show-unsigned-extensions-button =
+    .label = Nid oedd modd dilysu rhai estyniadau
+show-all-extensions-button =
+    .label = Dangos pob estyniad
+cmd-show-details =
+    .label = Dangos Rhagor o Wybodaeth
+    .accesskey = D
+cmd-find-updates =
+    .label = Canfod Diweddariadau
+    .accesskey = C
+cmd-preferences =
+    .label =
+        { PLATFORM() ->
+            [windows] Dewisiadau
+           *[other] Dewisiadau
+        }
+    .accesskey =
+        { PLATFORM() ->
+            [windows] D
+           *[other] e
+        }
+cmd-enable-theme =
+    .label = Gwisgo Thema
+    .accesskey = w
+cmd-disable-theme =
+    .label = Peidio Gwisgo Thema
+    .accesskey = P
+cmd-install-addon =
+    .label = Gosod
+    .accesskey = G
+cmd-contribute =
+    .label = Cyfrannu
+    .accesskey = C
+    .tooltiptext = Cyfrannu i ddatblygiad yr ychwanegyn
+detail-version =
+    .label = Fersiwn
+detail-last-updated =
+    .label = Diweddarwyd Diwethaf
+detail-contributions-description = Mae datblygwr yr ychwanegyn yn gofyn eich bod yn cynorthwyo i gefnogi datblygiad drwy wneud cyfraniad bychan.
+detail-contributions-button = Cyfrannu
+    .title = Cyfrannwch i ddatblygiad yr ategyn hwn
+    .accesskey = C
+detail-update-type =
+    .value = Diweddariadau Awtomatig
+detail-update-default =
+    .label = Rhagosodedig
+    .tooltiptext = Gosod diweddariadau'n awtomatig os mai dyna yw'r rhagosodedig
+detail-update-automatic =
+    .label = Ymlaen
+    .tooltiptext = Gosod diweddariadau'n awtomatig
+detail-update-manual =
+    .label = Diffodd
+    .tooltiptext = Peidio gosod diweddariadau'n awtomatig
+# Used as a description for the option to allow or block an add-on in private windows.
+detail-private-browsing-label = Rhedeg mewn Ffenestri Preifat
+# Some add-ons may elect to not run in private windows by setting incognito: not_allowed in the manifest.  This
+# cannot be overridden by the user.
+detail-private-disallowed-label = Heb ei ganiatáu mewn Ffenestri Preifat
+detail-private-disallowed-description2 = Nid yw'r estyniad hwn yn rhedeg tra'n pori'n preifat. <a data-l10n-name="learn-more">Dysgu rhagor</a>
+# Some special add-ons are privileged, run in private windows automatically, and this permission can't be revoked
+detail-private-required-label = Angen Mynediad i Ffenestri Preifat
+detail-private-required-description2 = Mae gan yr estyniad hwn fynediad i'ch gweithgareddau ar-lein wrth bori'n breifat. <a data-l10n-name="learn-more">Dysgu mwy</a>
+detail-private-browsing-on =
+    .label = Caniatáu
+    .tooltiptext = Caniatáu wrth Bori Preifat
+detail-private-browsing-off =
+    .label = Peidio Caniatáu
+    .tooltiptext = Analluogi mewn Pori Preifat
+detail-home =
+    .label = Tudalen Cartref
+detail-home-value =
+    .value = { detail-home.label }
+detail-repository =
+    .label = Proffil Ychwanegyn
+detail-repository-value =
+    .value = { detail-repository.label }
+detail-check-for-updates =
+    .label = Gwirio am Ddiweddariadau
+    .accesskey = G
+    .tooltiptext = Gwirio am ddiweddariad i'r ychwanegyn
+detail-show-preferences =
+    .label =
+        { PLATFORM() ->
+            [windows] Dewisiadau
+           *[other] Dewisiadau
+        }
+    .accesskey =
+        { PLATFORM() ->
+            [windows] D
+           *[other] e
+        }
+    .tooltiptext =
+        { PLATFORM() ->
+            [windows] Newid dewisiadau'r ychwanegyn
+           *[other] Newid dewisiadau'r ychwanegyn
+        }
+detail-rating =
+    .value = Graddio
+addon-restart-now =
+    .label = Ailgychwyn nawr
+disabled-unsigned-heading =
+    .value = Mae rhai ychwanegion wedi eu hanalluogi
+disabled-unsigned-description = Mae'r ychwanegion canlynol wedi eu dilysu i'w defnyddio yn { -brand-short-name }. Gallwch <label data-l10n-name="find-addons">canfod newidiadau</label> neu ofyn i'r datblygwr iddynt gael eu dilysu.
+disabled-unsigned-learn-more = Dysgu rhagor am ein hymdrechion i'ch cadw'n ddiogel ar-lein.
+disabled-unsigned-devinfo = Gall ddatblygwyr sydd â diddordeb mewn dilysu eu hychwanegion barhau drwy ddarllen ein <label data-l10n-name="learn-more">canllawiau</label>.
+plugin-deprecation-description = Rhywbeth ar goll? Nid yw rhai ategion yn cael eu cynnal bellach gan { -brand-short-name }. <label data-l10n-name="learn-more">Dysgu Rhagor.</label>
+legacy-warning-show-legacy = Dangos hen estyniadau
+legacy-extensions =
+    .value = Hen Estyniadau
+legacy-extensions-description = Nid yw'r estyniadau hyn yn cyrraedd safonau cyfredol { -brand-short-name } ac mae nhw wedi cael eu diffodd. <label data-l10n-name="legacy-learn-more">Dysgu am y newidiadau i ychwanegion</label>
+private-browsing-description2 =
+    Mae { -brand-short-name } yn newid sut mae estyniadau'n gweithio o fewn pori preifat. Ni fydd unrhyw estyniadau newydd y byddwch chi'n eu hychwanegu at { -brand-short-name } yn rhedeg yn ragosodedig o fewn Ffenestri Prefat. Oni bai eich bod yn ei ganiatáu yn y gosodiadau, ni fydd estyniad yn gweithio wrth bori'n preifat, ac ni chaiff fynediad at eich gweithgareddau ar-lein yno. Rydym wedi gwneud y newid hwn i gadw eich pori preifat yn breifat.
+    <label data-l10n-name="private-browsing-learn-more">Dysgu sut i reoli gosodiadau estyniad.</label>
+addon-category-discover = Argymhellion
+addon-category-discover-title =
+    .title = Argymhellion
+addon-category-extension = Estyniadau
+addon-category-extension-title =
+    .title = Estyniadau
+addon-category-theme = Themâu
+addon-category-theme-title =
+    .title = Themâu
+addon-category-plugin = Ategion
+addon-category-plugin-title =
+    .title = Ategion
+addon-category-dictionary = Geiriaduron
+addon-category-dictionary-title =
+    .title = Geiriaduron
+addon-category-locale = Iaith
+addon-category-locale-title =
+    .title = Iaith
+addon-category-available-updates = Diweddariadau ar Gael
+addon-category-available-updates-title =
+    .title = Diweddariadau ar Gael
+addon-category-recent-updates = Diweddariadau Diweddar
+addon-category-recent-updates-title =
+    .title = Diweddariadau Diweddar
+
+## These are global warnings
+
+extensions-warning-safe-mode = Mae pob ychwanegyn wedi eu hanalluogi gan y modd diogel.
+extensions-warning-check-compatibility = Mae gwirio cydnawsedd ychwanegion wedi ei analluogi. Efallai fod gennych ychwanegion anghydnaws.
+extensions-warning-check-compatibility-button = Galluogi
+    .title = Galluogi gwirio cydnawsedd ychwanegion
+extensions-warning-update-security = Mae gwirio diogelwch diweddariad wedi ei analluogi. Efallai eich bod o dan fygythiad gan ddiweddariad.
+extensions-warning-update-security-button = Galluogi
+    .title = Galluogi gwirio diogelwch diweddariad ychwanegyn
+
+## Strings connected to add-on updates
+
+addon-updates-check-for-updates = Gwirio am Ddiweddariadau
+    .accesskey = G
+addon-updates-view-updates = Gweld Diweddariadau Diweddar
+    .accesskey = D
+
+# This menu item is a checkbox that toggles the default global behavior for
+# add-on update checking.
+
+addon-updates-update-addons-automatically = Diweddaru Ychwanegion yn Awtomatig
+    .accesskey = A
+
+## Specific add-ons can have custom update checking behaviors ("Manually",
+## "Automatically", "Use default global behavior"). These menu items reset the
+## update checking behavior for all add-ons to the default global behavior
+## (which itself is either "Automatically" or "Manually", controlled by the
+## extensions-updates-update-addons-automatically.label menu item).
+
+addon-updates-reset-updates-to-automatic = Ailosod Pob Ychwanegyn i'w Diweddaru'n Awtomatig
+    .accesskey = P
+addon-updates-reset-updates-to-manual = Ailosod Pob Ychwanegyn i Ddiweddaru gyda Llaw
+    .accesskey = L
+
+## Status messages displayed when updating add-ons
+
+addon-updates-updating = Diweddaru ychwanegion
+addon-updates-installed = Mae eich ychwanegion wedi eu diweddaru.
+addon-updates-none-found = Heb ganfod diweddariadau
+addon-updates-manual-updates-found = Gweld Diweddariadau ar Gael
+
+## Add-on install/debug strings for page options menu
+
+addon-install-from-file = Gosod Ychwanegyn o Ffeil…
+    .accesskey = G
+addon-install-from-file-dialog-title = Dewis ategyn i'w osod
+addon-install-from-file-filter-name = Ychwanegion
+addon-open-about-debugging = Dadfygio Ychwanegion
+    .accesskey = Y
+
+## Extension shortcut management
+
+# This is displayed in the page options menu
+addon-manage-extensions-shortcuts = Rheoli Estyniad Llwybrau Byr
+    .accesskey = R
+shortcuts-no-addons = Nid oes gennych unrhyw estyniadau wedi'u galluogi.
+shortcuts-no-commands = Nid oes gan yr estyniadau canlynol lwybrau byr:
+shortcuts-input =
+    .placeholder = Teipiwch llwybr byr
+shortcuts-browserAction2 = Cychwyn botwm bar offer
+shortcuts-pageAction = Cychwyn gweithred tudalen
+shortcuts-sidebarAction = Toglo'r bar ochr
+shortcuts-modifier-mac = Cynnwys Ctrl, Alt, neu ⌘
+shortcuts-modifier-other = Cynnwys Ctrl neu Alt
+shortcuts-invalid = Cyfuniad annilys
+shortcuts-letter = Teipiwch lythyr
+shortcuts-system = Methu anwybyddu llwybr byr { -brand-short-name }
+# String displayed in warning label when there is a duplicate shortcut
+shortcuts-duplicate = Llwybr byr dyblyg
+# String displayed when a keyboard shortcut is already assigned to more than one add-on
+# Variables:
+#   $shortcut (string) - Shortcut string for the add-on
+shortcuts-duplicate-warning-message = Mae { $shortcut } yn cael ei ddefnyddio fel llwybr byr mewn mwy nag un achos. Gall llwybrau byr dyblyg achosi ymddygiad annisgwyl.
+# String displayed when a keyboard shortcut is already used by another add-on
+# Variables:
+#   $addon (string) - Name of the add-on
+shortcuts-exists = Ar waith eisoes gan { $addon }
+shortcuts-card-expand-button =
+    { $numberToShow ->
+        [zero] Dangos { $numberToShow } yn Rhagor
+        [one] Dangos { $numberToShow } yn Rhagor
+        [two] Dangos { $numberToShow } yn Rhagor
+        [few] Dangos { $numberToShow } yn Rhagor
+        [many] Dangos { $numberToShow } yn Rhagor
+       *[other] Dangos { $numberToShow } yn Rhagor
+    }
+shortcuts-card-collapse-button = Dangos Llai
+header-back-button =
+    .title = Mynd nôl
+
+## Recommended add-ons page
+
+# Explanatory introduction to the list of recommended add-ons. The action word
+# ("recommends") in the final sentence is a link to external documentation.
+discopane-intro =
+    Mae estyniadau a themâu yn debyg i apiau ar gyfer eich porwr, ac maen nhw'n gadael i chi
+    diogelu cyfrineiriau, llwytho fideos i lawr, dod o hyd i gytundebau, rhwystro hysbysebion blin, newid
+    golwg eich porwr a llawer mwy. Mae'r rhaglenni meddalwedd bach hyn fel arfer yn cael eu datblygu gan drydydd parti. Dyma detholiad y mae { -brand-product-name }<a data-l10n-name="learn-more-trigger">
+    yn eu hargymell </a> am ddiogelwch, perfformiad, a swyddogaethau gwell.
+# Notice to make user aware that the recommendations are personalized.
+discopane-notice-recommendations =
+    Mae rhai o'r argymhellion hyn wedi'u dewis yn benodol ar eich cyfer chi. Maen nhw'n seiliedig ar 
+    estyniadau eraill rydych chi wedi'u gosod, eich proffil dewisiadau, a'ch ystadegau defnydd.
+discopane-notice-learn-more = Dysgu rhagor
+privacy-policy = Polisi Preifatrwydd
+# Refers to the author of an add-on, shown below the name of the add-on.
+# Variables:
+#   $author (string) - The name of the add-on developer.
+created-by-author = gan <a data-l10n-name="author">{ $author }</a>
+# Shows the number of daily users of the add-on.
+# Variables:
+#   $dailyUsers (number) - The number of daily users.
+user-count = Defnyddwyr: { $dailyUsers }
+install-extension-button = Ychwanegu at { -brand-product-name }
+install-theme-button = Gosod Thema
+# The label of the button that appears after installing an add-on. Upon click,
+# the detailed add-on view is opened, from where the add-on can be managed.
+manage-addon-button = Rheoli
+find-more-addons = Canfod rhagor o ychwanegion
+# This is a label for the button to open the "more options" menu, it is only
+# used for screen readers.
+addon-options-button =
+    .aria-label = Rhagor o Ddewisiadau
+
+## Add-on actions
+
+report-addon-button = Adrodd
+remove-addon-button = Tynnu
+# The link will always be shown after the other text.
+remove-addon-disabled-button = Methu ei Dynnu <a data-l10n-name="link"> Pam? </a>
+disable-addon-button = Analluogu
+enable-addon-button = Galluogi
+# This is used for the toggle on the extension card, it's a checkbox and this
+# is always its label.
+extension-enable-addon-button-label =
+    .aria-label = Galluogi
+preferences-addon-button =
+    { PLATFORM() ->
+        [windows] Opsiynau
+       *[other] Dewisiadau
+    }
+details-addon-button = Manylion
+release-notes-addon-button = Nodiadau Rhyddhau
+permissions-addon-button = Caniatâd
+extension-enabled-heading = Galluogwyd
+extension-disabled-heading = Analluogwyd
+theme-enabled-heading = Galluogwyd
+theme-disabled-heading = Analluogwyd
+plugin-enabled-heading = Galluogwyd
+plugin-disabled-heading = Analluogwyd
+dictionary-enabled-heading = Galluogwyd
+dictionary-disabled-heading = Analluogwyd
+locale-enabled-heading = Galluogwyd
+locale-disabled-heading = Analluogwyd
+ask-to-activate-button = Gofyn i'w Weithredu
+always-activate-button = Gweithredu Bob Tro
+never-activate-button = Byth Gweithredu
+addon-detail-author-label = Awdur
+addon-detail-version-label = Fersiwn
+addon-detail-last-updated-label = Diweddarwyd Diwethaf
+addon-detail-homepage-label = Tudalen Cartref
+addon-detail-rating-label = Graddio
+# Message for add-ons with a staged pending update.
+install-postponed-message = Bydd yr estyniad hwn yn cael ei ddiweddaru pan fydd { -brand-short-name } yn ailgychwyn.
+install-postponed-button = Diweddaru Nawr
+# The average rating that the add-on has received.
+# Variables:
+#   $rating (number) - A number between 0 and 5. The translation should show at most one digit after the comma.
+five-star-rating =
+    .title = Graddiwyd { NUMBER($rating, maximumFractionDigits: 1) } allan o 5
+# This string is used to show that an add-on is disabled.
+# Variables:
+#   $name (string) - The name of the add-on
+addon-name-disabled = { $name } (analluogwyd)
+# The number of reviews that an add-on has received on AMO.
+# Variables:
+#   $numberOfReviews (number) - The number of reviews received
+addon-detail-reviews-link =
+    { $numberOfReviews ->
+        [zero] { $numberOfReviews } adolygiad
+        [one] { $numberOfReviews } adolygiad
+        [two] { $numberOfReviews } adolygiad
+        [few] { $numberOfReviews } adolygiad
+        [many] { $numberOfReviews } adolygiad
+       *[other] { $numberOfReviews } adolygiad
+    }
+
+## Pending uninstall message bar
+
+# Variables:
+#   $addon (string) - Name of the add-on
+pending-uninstall-description = Mae <span data-l10n-name="addon-name">{ $addon }</span> wedi ei dynnu.
+pending-uninstall-undo-button = Dadwneud
+addon-detail-updates-label = Caniatáu diweddariadau awtomatig
+addon-detail-updates-radio-default = Rhagosodedig
+addon-detail-updates-radio-on = Ymlaen
+addon-detail-updates-radio-off = Diffodd
+addon-detail-update-check-label = Gwirio am Ddiweddariadau
+install-update-button = Diweddaru
+# This is the tooltip text for the private browsing badge in about:addons. The
+# badge is the private browsing icon included next to the extension's name.
+addon-badge-private-browsing-allowed2 =
+    .title = Caniatáu mewn ffenestri preifat
+    .aria-label = { addon-badge-private-browsing-allowed2.title }
+addon-detail-private-browsing-help = Pan mae'n cael ei ganiatáu, bydd yr estyniad ar gael i'ch gweithgareddau ar-lein tra byddwch yn pori'n breifat. <a data-l10n-name="learn-more"> Gwybod rhagor</a>
+addon-detail-private-browsing-allow = Caniatáu
+addon-detail-private-browsing-disallow = Peidio Caniatáu
+
+## This is the tooltip text for the recommended badges for an extension in about:addons. The
+## badge is a small icon displayed next to an extension when it is recommended on AMO.
+
+addon-badge-recommended2 =
+    .title = Dim ond estyniadau sy'n cwrdd â'n safonau ar gyfer diogelwch a pherfformiad y mae { -brand-product-name } yn eu hargymell
+    .aria-label = { addon-badge-recommended2.title }
+addon-badge-line2 =
+    .title = Crëwyd yr estyniad swyddogol hwn gan wneuthurwyr { -brand-product-name }
+    .aria-label = { addon-badge-line2.title }
+# We hard code "Mozilla" in the string below because the extensions are built
+# by Mozilla and we don't want forks to display "by Fork".
+addon-badge-line3 =
+    .title = Estyniad swyddogol wedi'i adeiladu gan Mozilla. Mae'n cydfynd â safonau diogelwch a pherfformiad
+    .aria-label = { addon-badge-line3.title }
+addon-badge-verified2 =
+    .title = Mae'r estyniad hwn wedi'i adolygu i fodloni ein safonau ar gyfer diogelwch a pherfformiad
+    .aria-label = { addon-badge-verified2.title }
+
+##
+
+available-updates-heading = Diweddariadau ar Gael
+recent-updates-heading = Diweddariadau Diweddar
+release-notes-loading = Llwytho…
+release-notes-error = Ymddiheuriadau ond bu gwall llwytho'r nodiadau ryddhau.
+addon-permissions-empty = Nid oes angen unrhyw ganiatâd ar yr estyniad hwn
+addon-permissions-required = Caniatâd angenrheidiol y swyddogaethau craidd:
+addon-permissions-optional = Caniatâd dewisol ar gyfer y swyddogaethau ychwanegol:
+addon-permissions-learnmore = Dysgu rhagor am ganiatâd
+recommended-extensions-heading = Estyniadau Cymeradwy
+recommended-themes-heading = Themâu Cymeradwy
+# A recommendation for the Firefox Color theme shown at the bottom of the theme
+# list view. The "Firefox Color" name itself should not be translated.
+recommended-theme-1 = Teimlo'n greadigol? <a data-l10n-name="link">Adeiladwch eich thema eich hun gyda Firefox Color. </a>
+
+## Page headings
+
+extension-heading = Rheoli eich estyniadau
+theme-heading = Rheoli eich themâu
+plugin-heading = Rheoli eich ategion
+dictionary-heading = Rheoli eich geiriaduron
+locale-heading = Rheoli eich ieithoedd
+updates-heading = Rheoli Eich Diweddariadau
+discover-heading = Personoli Eich { -brand-short-name }
+shortcuts-heading = Rheoli Estyniad Llwybrau Byr
+default-heading-search-label = Canfod rhagor o ychwanegion
+addons-heading-search-input =
+    .placeholder = Search addons.mozilla.org
+addon-page-options-button =
+    .title = Offer ar gyfer pob ychwanegyn
diff --git a/l10n-cy/toolkit/toolkit/about/aboutCompat.ftl b/l10n-cy/toolkit/toolkit/about/aboutCompat.ftl
new file mode 100644
index 0000000000..e4e3ee332e
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/about/aboutCompat.ftl
@@ -0,0 +1,13 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+label-disable = analluogi
+label-enable = Galluogi
+label-interventions = Ymyriadau
+label-more-information = Rhagor o Wybodaeth: Byg { $bug }
+label-overrides = Tros reolaeth Asiant Defnyddiwr
+text-disabled-in-about-config = Mae'r nodwedd hon wedi ei analluogi yn about:config
+text-no-interventions = Nid oes ymyriadau yn cael eu defnyddio
+text-no-overrides = Nid oes unrhyw ymyriadau UA yn cael eu defnyddio
+text-title = about:compat
diff --git a/l10n-cy/toolkit/toolkit/about/aboutConfig.ftl b/l10n-cy/toolkit/toolkit/about/aboutConfig.ftl
new file mode 100644
index 0000000000..dfbe5f46fa
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/about/aboutConfig.ftl
@@ -0,0 +1,109 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+config-window =
+    .title = about:config
+
+## Strings used to display a warning in about:config
+
+# This text should be attention grabbing and playful
+config-about-warning-title =
+    .value = Gall hyn ddiddymu eich gwarant!
+config-about-warning-text = Gall newid y gosodiadau uwch wneud niwed i sefydlogrwydd a pherfformiad y rhaglen. Dylech barhau dim ond os ydych yn gwybod beth rydych yn ei wneud.
+config-about-warning-button =
+    .label = Rwy'n deall y peryglon!
+config-about-warning-checkbox =
+    .label = Dangos y rhybudd y tro nesaf
+
+config-search-prefs =
+    .value = Chwilio:
+    .accesskey = C
+
+config-focus-search =
+    .key = r
+
+config-focus-search-2 =
+    .key = f
+
+## These strings are used for column headers
+
+config-pref-column =
+    .label = Enw'r Dewis
+config-lock-column =
+    .label = Statws
+config-type-column =
+    .label = Math
+config-value-column =
+    .label = Gwerth
+
+## These strings are used for tooltips
+
+config-pref-column-header =
+    .tooltip = Clicio i'w trefnu
+config-column-chooser =
+    .tooltip = Cliciwch i ddewis colofnau i'w dangos
+
+## These strings are used for the context menu
+
+config-copy-pref =
+    .key = C
+    .label = Copïo
+    .accesskey = C
+
+config-copy-name =
+    .label = Copïo Enw
+    .accesskey = n
+
+config-copy-value =
+    .label = Copïo Gwerth
+    .accesskey = G
+
+config-modify =
+    .label = Newid
+    .accesskey = e
+
+config-toggle =
+    .label = Toglo
+    .accesskey = T
+
+config-reset =
+    .label = Ailosod
+    .accesskey = A
+
+config-new =
+    .label = Newydd
+    .accesskey = N
+
+config-string =
+    .label = Llinyn
+    .accesskey = L
+
+config-integer =
+    .label = Cyfanrif
+    .accesskey = i
+
+config-boolean =
+    .label = Booleaidd
+    .accesskey = B
+
+config-default = rhagosodiad
+config-modified = newidwyd
+config-locked = cloi
+
+config-property-string = llinyn
+config-property-int = cyfanrif
+config-property-bool = booleaidd
+
+config-new-prompt = Rhoi enw blaenoriaeth
+
+config-nan-title = Gwerth annilys
+config-nan-text = Nid yw'r testun a gyflwynwyd yn rif.
+
+# Variables:
+#   $type (String): type of value (boolean, integer or string)
+config-new-title = Gwerth newydd { $type }
+
+# Variables:
+#   $type (String): type of value (boolean, integer or string)
+config-modify-title = Rhoi gwerth { $type }
diff --git a/l10n-cy/toolkit/toolkit/about/aboutGlean.ftl b/l10n-cy/toolkit/toolkit/about/aboutGlean.ftl
new file mode 100644
index 0000000000..7c6def3a91
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/about/aboutGlean.ftl
@@ -0,0 +1,15 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+### "Glean" and "Glean SDK" should remain in English.
+
+about-glean-page-title = Ynghylch Glean
+about-glean-description = Mae'r <a data-l10n-name="glean-sdk-doc-link">Glean SDK</a> yn llyfrgell casglu data sy'n cael ei ddefnyddio o fewn cynnyrch Mozilla. Mae'r dudalen hon ar gyfer datblygwyr a phrofwyr sydd angen <a data-l10n-name="fog-debug-doc-link">ffurfweddu dadfygio a chyflwr cofnodi'r Glean SDK </a>.
+about-glean-warning = Gall camddefnyddio'r rhyngwyneb hwn chwalu { -brand-short-name }.
+
+tag-pings-label = Tagiwch bob pingiadau a anfonwyd gyda'r tag hwn
+log-pings-label = Cofnodi llwythi ping cyn anfon?
+send-pings-label = Anfon y ping a enwyd
+controls-button-label = Cyflwyno Gosodiadau
diff --git a/l10n-cy/toolkit/toolkit/about/aboutHttpsOnlyError.ftl b/l10n-cy/toolkit/toolkit/about/aboutHttpsOnlyError.ftl
new file mode 100644
index 0000000000..36ed03dda3
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/about/aboutHttpsOnlyError.ftl
@@ -0,0 +1,28 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+about-httpsonly-insecure-title = Nid yw'r Cysylltiad Diogel ar Gael
+# Variables:
+#   $websiteUrl (String) - Url of the website that failed to load. Example: www.example.com
+about-httpsonly-insecure-explanation-unavailable = Rydych yn pori yn y modd HTTPS-Only Mode, ac nid oes fersiwn HTTPS ddiogel o <em>{ $websiteUrl }</em> ar gael.
+about-httpsonly-insecure-explanation-reasons = Yn fwyaf tebygol, nid yw'r wefan yn cefnogi HTTPS, ond mae hefyd yn bosibl bod ymosodwr yn rhwystro'r fersiwn HTTPS.
+about-httpsonly-insecure-explanation-exception = Er bod y risg diogelwch yn isel, os penderfynwch ymweld â fersiwn HTTP y wefan, peidiwch nodi unrhyw wybodaeth sensitif fel cyfrineiriau, e-byst, neu fanylion cardiau credyd.
+about-httpsonly-button-make-exception = Derbyn y Risg a Pharhau i'r Wefan
+about-httpsonly-title = Mae { -brand-short-name } wedi canfod Mater Diogelwch Posibl
+# Variables:
+#   $websiteUrl (String) - Url of the website that failed to load. Example: www.example.com
+about-httpsonly-explanation-unavailable = Rydych yn pori yn y modd HTTPS-Only Mode, ac nid oes fersiwn HTTPS ddiogel o <em>{ $websiteUrl }</em> ar gael.
+about-httpsonly-title-alert = Rhybudd Modd HTTPS-yn-Unig
+about-httpsonly-title-connection-not-available = Nid yw'r Cysylltiad Diogel ar Gael
+# Variables:
+#   $websiteUrl (String) - Url of the website that failed to load. Example: www.example.com
+about-httpsonly-explanation-unavailable2 = Rydych wedi galluogi'r Modd HTTPS-yn-Unig ar gyfer gwell diogelwch, ac nid oes fersiwn HTTPS o <em>{ $websiteUrl }</em> ar gael.
+about-httpsonly-explanation-question = Beth allai fod yn achosi hyn?
+about-httpsonly-explanation-nosupport = Yn fwyaf tebygol, nid yw'r wefan yn cefnogi HTTPS.
+about-httpsonly-explanation-risk = Mae hefyd yn bosibl bod ymosodwr yn ceisio ymyrryd. Os penderfynwch ymweld â'r wefan, peidiwch â rhannu unrhyw fanylion sensitif fel cyfrineiriau, e-byst, neu fanylion cardiau credyd.
+about-httpsonly-button-accept-and-continue = Derbyn y Perygl a Pharhau
+about-httpsonly-explanation-continue = Os byddwch yn parhau, bydd y Modd HTTPS-yn-Unig yn cael ei ddiffodd dros dro ar gyfer y wefan hon.
+about-httpsonly-button-continue-to-site = Ymlaen i'r Wefan HTTP
+about-httpsonly-button-go-back = Mynd Nôl
+about-httpsonly-link-learn-more = Dysgu Rhagor…
diff --git a/l10n-cy/toolkit/toolkit/about/aboutMozilla.ftl b/l10n-cy/toolkit/toolkit/about/aboutMozilla.ftl
new file mode 100644
index 0000000000..411039d846
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/about/aboutMozilla.ftl
@@ -0,0 +1,11 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+about-mozilla-title-6-27 = Llyfr Mozilla, 6:27
+about-mozilla-quote-6-27 =
+    The Beast continued its studies with renewed <em>Focus</em>, building great <em>Reference</em>
+    works and contemplating new <em>Realities</em>. The Beast brought forth its followers and
+    acolytes to create a renewed smaller form of itself and, through <em>Mischievous</em> means,
+    sent it out across the world.
+about-mozilla-from-6-27 = o <strong>Lyfr Mozilla,</strong> 6:27
diff --git a/l10n-cy/toolkit/toolkit/about/aboutNetworking.ftl b/l10n-cy/toolkit/toolkit/about/aboutNetworking.ftl
new file mode 100644
index 0000000000..f6a1eea82e
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/about/aboutNetworking.ftl
@@ -0,0 +1,71 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+about-networking-title = Ynghylch Rhwydweithio
+about-networking-http = HTTP
+about-networking-sockets = Socedi
+about-networking-dns = DNS
+about-networking-dns-clear-cache-button = Clirio'r Storfa DNS
+about-networking-dns-trr-url = URL DoH
+about-networking-dns-suffix = Ôl-ddodiad DNS
+about-networking-websockets = WebSockets
+about-networking-refresh = Adnewyddu
+about-networking-auto-refresh = Adnewyddu pob 3 eiliad
+about-networking-hostname = Enw Gwesteiwr
+about-networking-port = Porth
+about-networking-http-version = Fersiwn HTTP
+about-networking-ssl = SSL
+about-networking-active = Gweithredol
+about-networking-idle = Segur
+about-networking-host = Gwesteiwr
+about-networking-tcp = TCP
+about-networking-sent = Anfonwyd
+about-networking-received = Derbyniwyd
+about-networking-family = Teulu
+about-networking-trr = TRR
+about-networking-addresses = Cyfeiriad
+about-networking-expires = Daw i ben (Eiliadau)
+about-networking-originAttributesSuffix = Allwedd Ynysu
+about-networking-messages-sent = Negeseuon Anfonwyd
+about-networking-messages-received = Negeseuon Derbyniwyd
+about-networking-bytes-sent = Didau Wedi'u Hanfon
+about-networking-bytes-received = Didau Wedi'u Derbyn
+about-networking-logging = Cofnodi
+about-networking-log-tutorial = Gw <a data-l10n-name="logging">HTTP Logging</a> am wybodaeth ar sut i ddefnyddio'r teclyn hwn.
+about-networking-current-log-file = Ffeil Cofnodi Cyfredol:
+about-networking-current-log-modules = Modiwlau Cofnodi Cyfredol:
+about-networking-set-log-file = Gosod Ffeil Cofnodi
+about-networking-set-log-modules = Gosod Modiwlau Cofnodi
+about-networking-start-logging = Cychwyn Cofnodi
+about-networking-stop-logging = Peidio Cofnodi
+about-networking-dns-lookup = Chwilio DNS
+about-networking-dns-lookup-button = Datrys
+about-networking-dns-domain = Parth:
+about-networking-dns-lookup-table-column = IPau
+about-networking-dns-https-rr-lookup-table-column = HTTP RRs
+about-networking-rcwn = Statws RCWN
+about-networking-rcwn-status = Statws RCWN
+about-networking-rcwn-cache-won-count = Cyfrif storfa dros dro wedi ei ennill
+about-networking-rcwn-net-won-count = Cyfrif rhwyd wedi ei ennill
+about-networking-total-network-requests = Cyfanswm cyfrif ceisiadau rhwydwaith
+about-networking-rcwn-operation = Gweithred Storfa Dros Dro
+about-networking-rcwn-perf-open = Ar Agor
+about-networking-rcwn-perf-read = Darllen
+about-networking-rcwn-perf-write = Ysgrifennu
+about-networking-rcwn-perf-entry-open = Cofnod Ar Agor
+about-networking-rcwn-avg-short = Cyfartaledd Hir
+about-networking-rcwn-avg-long = Cyfartaledd Hir
+about-networking-rcwn-std-dev-long = Gwyriad Safonol Hir
+about-networking-rcwn-cache-slow = Cyfrif araf storfa dros dro
+about-networking-rcwn-cache-not-slow = Cyfrif nid araf storfa dros dro
+about-networking-networkid = ID Rhwydwaith
+about-networking-networkid-id = ID Rhwydwaith
+
+## Link is intended as "network link"
+
+about-networking-networkid-is-up = Mae'r cyswllt ar i fyny
+about-networking-networkid-status-known = Mae statws y cyswllt yn hysbys
+
+##
+
diff --git a/l10n-cy/toolkit/toolkit/about/aboutPerformance.ftl b/l10n-cy/toolkit/toolkit/about/aboutPerformance.ftl
new file mode 100644
index 0000000000..cf5b3270e2
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/about/aboutPerformance.ftl
@@ -0,0 +1,67 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# Page title
+about-performance-title = Rheolwr Tasgau
+
+## Column headers
+
+column-name = Enw
+column-type = Math
+column-energy-impact = Effaith Ynni
+column-memory = Cof
+
+## Special values for the Name column
+
+ghost-windows = Tabiau Wedi'u Cau'n Ddiweddar
+# Variables:
+#   $title (String) - the title of the preloaded page, typically 'New Tab'
+preloaded-tab = Rhaglwytho: { $title }
+
+## Values for the Type column
+
+type-tab = Tab
+type-subframe = Is-ffrâm
+type-tracker = Traciwr
+type-addon = Ychwanegyn
+type-browser = Porwr
+type-worker = Gweithiwr
+type-other = Arall
+
+## Values for the Energy Impact column
+##
+## Variables:
+##   $value (Number) - Value of the energy impact, eg. 0.25 (low),
+##                     5.38 (medium), 105.38 (high)
+
+energy-impact-high = Uchel ({ $value })
+energy-impact-medium = Canolig ({ $value })
+energy-impact-low = Isel ({ $value })
+
+## Values for the Memory column
+##
+## Variables:
+##   $value (Number) - How much memory is used
+
+size-KB = { $value } KB
+size-MB = { $value } MB
+size-GB = { $value } GB
+
+## Tooltips for the action buttons
+
+close-tab =
+    .title = Cau tab
+show-addon =
+    .title = Dangos yn y Rheolwr Ychwanegion
+
+# Tooltip when hovering an item of the about:performance table
+# Variables:
+#   $totalDispatches (Number) - how many dispatches occured for this page since it loaded
+#   $totalDuration (Number) - how much CPU time was used by this page since it loaded
+#   $dispatchesSincePrevious (Number) - how many dispatches occured in the last 2 seconds
+#   $durationSincePrevious (Number) - how much CPU time was used in the last 2 seconds
+item =
+    .title =
+        Negeseuon ers llwytho: { $totalDispatches } ({ $totalDuration } ms)
+        Negeseuon yn yr eiliadau diwethaf: { $dispatchesSincePrevious } ({ $durationSincePrevious } ms)
diff --git a/l10n-cy/toolkit/toolkit/about/aboutPlugins.ftl b/l10n-cy/toolkit/toolkit/about/aboutPlugins.ftl
new file mode 100644
index 0000000000..3f0e67144f
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/about/aboutPlugins.ftl
@@ -0,0 +1,35 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+title-label = Ynghylch Ategion
+
+installed-plugins-label = Ategion wedi eu gosod
+no-plugins-are-installed-label = Heb ganfod ategion wedi eu gosod
+
+deprecation-description = Colli rhywbeth? Nid yw rhai ategion yn cael eu cynnal. <a data-l10n-name="deprecation-link">Dysgu Rhagor.</a>
+
+## The information of plugins
+##
+## Variables:
+##   $pluginLibraries: the plugin library
+##   $pluginFullPath: path of the plugin
+##   $version: version of the plugin
+
+file-dd = <span data-l10n-name="file">Ffeil:</span> { $pluginLibraries }
+path-dd = <span data-l10n-name="path">Llwybr:</span> { $pluginFullPath }
+version-dd = <span data-l10n-name="version">Fersiwn:</span> { $version }
+
+## These strings describe the state of plugins
+##
+## Variables:
+##   $blockListState: show some special state of the plugin, such as blocked, outdated
+
+state-dd-enabled = <span data-l10n-name="state">Sir/Talaith:</span> Galluogwyd
+state-dd-enabled-block-list-state = <span data-l10n-name="state">Sir/Talaith:</span> Galluogwyd ({ $blockListState })
+state-dd-Disabled = <span data-l10n-name="state">Sir/Talaith:</span> Analluogwyd
+state-dd-Disabled-block-list-state = <span data-l10n-name="state">Sir/Talaith:</span> Analluogwyd ({ $blockListState })
+
+mime-type-label = Math MIME
+description-label = Disgrifiad
+suffixes-label = Rhagosodiad
diff --git a/l10n-cy/toolkit/toolkit/about/aboutProcesses.ftl b/l10n-cy/toolkit/toolkit/about/aboutProcesses.ftl
new file mode 100644
index 0000000000..6bb170b113
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/about/aboutProcesses.ftl
@@ -0,0 +1,133 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# Page title
+about-processes-title = Rheolwr Prosesau
+# The Actions column
+about-processes-column-action =
+    .title = Gweithredoedd
+
+## Tooltips
+
+about-processes-shutdown-process =
+    .title = Dadlwytho tabiau a lladd y broses
+about-processes-shutdown-tab =
+    .title = Cau tab
+
+## Column headers
+
+about-processes-column-name = Enw
+about-processes-column-memory-resident = Cof
+about-processes-column-cpu-total = CPU
+
+## Process names
+## Variables:
+##    $pid (String) The process id of this process, assigned by the OS.
+##    $origin (String) The domain name for this process.
+##    $type (String) The raw type for this process. Used for unknown processes.
+
+about-processes-browser-process-name = (proses { $pid }) { -brand-short-name }
+about-processes-web-process-name = Gwe (proses { $pid }, wedi'i rannu)
+about-processes-web-isolated-process-name = Gwe (proses { $pid }) ar gyfer { $origin }
+about-processes-web-large-allocation = Gwe (proses { $pid }, mawr) ar gyfer { $origin }
+about-processes-with-coop-coep-process-name = Gwe (proses { $pid }, traws-darddiad ynyswyd) ar gyfer { $origin }
+about-processes-file-process-name = Ffeiliau (proses { $pid })
+about-processes-extension-process-name = Estyniadau (proses { $pid })
+about-processes-privilegedabout-process-name = Ynghylch (proses { $pid })
+about-processes-plugin-process-name = Ategion (proses { $pid })
+about-processes-privilegedmozilla-process-name = Gwe (proses { $pid }) ar gyfer gwefannau { -vendor-short-name }
+about-processes-gmp-plugin-process-name = Ategion Cyfryngau Gecko (proses { $pid })
+about-processes-gpu-process-name = GPU (proses { $pid })
+about-processes-vr-process-name = VR (proses { $pid })
+about-processes-rdd-process-name = Datgodiwr Data (proses { $pid })
+about-processes-socket-process-name = Rhwydwaith (proses { $pid })
+about-processes-remote-sandbox-broker-process-name = Brocer Blwch Tywod Pell (proses { $pid })
+about-processes-fork-server-process-name = Gweinydd Fforc (proses { $pid })
+about-processes-preallocated-process-name = Rhag-ddyrannwyd (proses { $pid })
+about-processes-unknown-process-name = Arall ({ $type }, proses { $pid })
+# Process
+# Variables:
+#   $name (String) The name assigned to the process.
+#   $pid (String) The process id of this process, assigned by the OS.
+about-processes-process-name = Proses { $pid }: { $name }
+
+## Details within processes
+
+# Single-line summary of threads
+# Variables:
+#    $number (Number) The number of threads in the process. Typically larger
+#                     than 30. We don't expect to ever have processes with less
+#                     than 5 threads.
+about-processes-thread-summary = Trywyddau ({ $number })
+# Thread details
+# Variables:
+#   $name (String) The name assigned to the thread.
+#   $tid (String) The thread id of this thread, assigned by the OS.
+about-processes-thread-name = Trywydd { $tid }: { $name }
+# Tab
+# Variables:
+#   $name (String) The name of the tab (typically the title of the page, might be the url while the page is loading).
+about-processes-tab-name = Tab: { $name }
+about-processes-preloaded-tab = Tab Newydd wedi'i Rhag-lwytho
+# Single subframe
+# Variables:
+#   $url (String) The full url of this subframe.
+about-processes-frame-name-one = Is-ffrâm: { $url }
+# Group of subframes
+# Variables:
+#   $number (Number) The number of subframes in this group. Always ≥ 1.
+#   $shortUrl (String) The shared prefix for the subframes in the group.
+about-processes-frame-name-many = Is-fframiau ({ $number }): { $shortUrl }
+
+## Displaying CPU (percentage and total)
+## Variables:
+##    $percent (Number) The percentage of CPU used by the process or thread.
+##                      Always > 0, generally <= 200.
+##    $total (Number) The amount of time used by the process or thread since
+##                    its start.
+##    $unit (String) The unit in which to display $total. See the definitions
+##                   of `duration-unit-*`.
+
+# Common case.
+about-processes-cpu-user-and-kernel = { NUMBER($percent, maximumSignificantDigits: 2, style: "percent") } ({ NUMBER($total, maximumFractionDigits: 0) }{ $unit })
+# Special case: data is not available yet.
+about-processes-cpu-user-and-kernel-not-ready = (yn mesur)
+# Special case: process or thread is currently idle.
+about-processes-cpu-user-and-kernel-idle = segur ({ NUMBER($total, maximumFractionDigits: 2) }{ $unit })
+
+## Displaying Memory (total and delta)
+## Variables:
+##    $total (Number) The amount of memory currently used by the process.
+##    $totalUnit (String) The unit in which to display $total. See the definitions
+##                        of `memory-unit-*`.
+##    $delta (Number) The absolute value of the amount of memory added recently.
+##    $deltaSign (String) Either "+" if the amount of memory has increased
+##                        or "-" if it has decreased.
+##    $deltaUnit (String) The unit in which to display $delta. See the definitions
+##                        of `memory-unit-*`.
+
+# Common case.
+about-processes-total-memory-size = { NUMBER($total, maximumFractionDigits: 0) }{ $totalUnit } ({ $deltaSign }{ NUMBER($delta, maximumFractionDigits: 0) }{ $deltaUnit })
+# Special case: no change.
+about-processes-total-memory-size-no-change = { NUMBER($total, maximumFractionDigits: 0) }{ $totalUnit }
+
+## Duration units
+
+duration-unit-ns = ns
+duration-unit-us = µs
+duration-unit-ms = ms
+duration-unit-s = e
+duration-unit-m = m
+duration-unit-h = a
+duration-unit-d = d
+
+## Memory units
+
+memory-unit-B = B
+memory-unit-KB = KB
+memory-unit-MB = MB
+memory-unit-GB = GB
+memory-unit-TB = TB
+memory-unit-PB = PB
+memory-unit-EB = EB
diff --git a/l10n-cy/toolkit/toolkit/about/aboutProfiles.ftl b/l10n-cy/toolkit/toolkit/about/aboutProfiles.ftl
new file mode 100644
index 0000000000..6f53902fcf
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/about/aboutProfiles.ftl
@@ -0,0 +1,74 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+profiles-title = Ynghylch Proffiliau
+profiles-subtitle = Mae'r dudalen hon yn eich helpu i reoli eich proffiliau. Mae pob proffil yn fyd ar wahân sy'n cynnwys hanes, nodau tudalen, gosodiadau ac yn ychwanegion gwahanol.
+profiles-create = Creu Proffil Newydd
+profiles-restart-title = Ailgychwyn
+profiles-restart-in-safe-mode = Ailgychwyn gydag Ychwanegion wedi eu Hanablu…
+profiles-restart-normal = Ailgychwyn fel arfer…
+profiles-conflict = Mae copi arall o { -brand-product-name } wedi gwneud newidiadau i broffiliau. Rhaid ailgychwyn { -brand-short-name } cyn gwneud mwy o newidiadau.
+profiles-flush-fail-title = Heb gadw'r newidiadau
+profiles-flush-conflict = { profiles-conflict }
+profiles-flush-failed = Mae gwall annisgwyl wedi atal eich newidiadau rhag cael eu cadw.
+profiles-flush-restart-button = Ailgychwyn { -brand-short-name }
+
+# Variables:
+#   $name (String) - Name of the profile
+profiles-name = Proffil: { $name }
+profiles-is-default = Proffil Ragosodedig
+profiles-rootdir = Cyfarwyddiadur Gwraidd
+
+# localDir is used to show the directory corresponding to
+# the main profile directory that exists for the purpose of storing data on the
+# local filesystem, including cache files or other data files that may not
+# represent critical user data. (e.g., this directory may not be included as
+# part of a backup scheme.)
+# In case localDir and rootDir are equal, localDir is not shown.
+profiles-localdir = Cyfarwyddiadur Lleol
+profiles-current-profile = Dyma'r proffil sy'n cael ei ddefnyddio ac nid oes modd ei ddileu.
+profiles-in-use-profile = Mae'r proffil yn cael ei ddefnyddio o fewn rhaglen arall ac nid oes modd ei ddileu.
+
+profiles-rename = Ailenwi
+profiles-remove = Tynnu
+profiles-set-as-default = Gosod fel y proffil ragosodedig
+profiles-launch-profile = Cychwyn proffil yn y porwr newydd
+
+profiles-cannot-set-as-default-title = Methu gosod y rhagosodedig
+profiles-cannot-set-as-default-message = Nid oes modd newid y proffil rhagosodedig am { -brand-short-name }.
+
+profiles-yes = iawn
+profiles-no = na
+
+profiles-rename-profile-title = Newid Enw Proffil
+# Variables:
+#   $name (String) - Name of the profile
+profiles-rename-profile = Ailenwi proffil { $name }
+
+profiles-invalid-profile-name-title = Enw proffil annilys
+# Variables:
+#   $name (String) - Name of the profile
+profiles-invalid-profile-name = Methu caniatáu enw proffil "{ $name }".
+
+profiles-delete-profile-title = Dileu Proffil
+# Variables:
+#   $dir (String) - Path to be displayed
+profiles-delete-profile-confirm =
+    Bydd dileu proffil yn tynnu'r proffil o'r rhestr o broffiliau sydd ar gael ac nid oes modd ei ddadwneud.
+    Gallwch hefyd ddewis i ddileu ffeiliau data proffil, gan gynnwys eich gosodiadau, tystysgrifau a data arall yn perthyn i ddefnyddwyr. Bydd y dewis hwn yn dileu ffolder "{ $dir }" ac nid oes modd ei ddadwneud.
+    Hoffech chi ddileu'r ffeiliau data proffil?
+profiles-delete-files = Dileu Ffeiliau
+profiles-dont-delete-files = Peidio Dileu Ffeiliau
+
+profiles-delete-profile-failed-title = Gwall
+profiles-delete-profile-failed-message = Bu gwall wrth geisio dileu'r proffil hwn.
+
+
+profiles-opendir =
+    { PLATFORM() ->
+        [macos] Dangos yn Finder
+        [windows] Agor Ffolder
+       *[other] Agor Cyfeiriadur
+    }
diff --git a/l10n-cy/toolkit/toolkit/about/aboutRights.ftl b/l10n-cy/toolkit/toolkit/about/aboutRights.ftl
new file mode 100644
index 0000000000..541a34c7f7
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/about/aboutRights.ftl
@@ -0,0 +1,36 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+rights-title = Ynghylch eich hawliau
+rights-intro = Mae { -brand-full-name } yn feddalwedd cod agored rhydd a rhad, wedi ei adeiladu gan gymuned o filoedd o bobl ar draws y byd i gyd. Mae yna rhai pethau i chi gael gwybod:
+rights-intro-point-1 = Mae { -brand-short-name } ar gael i chi o dan amodau'r <a data-l10n-name="mozilla-public-license-link">Trwydded Gyhoeddus Mozilla</a>. Mae hyn yn golygu y cewch ddefnyddio, gopïo a dosbarthu { -brand-short-name } i eraill.  Mae croeso i chi newid cod ffynhonnell { -brand-short-name } yn ôl eich angen. Mae Trwydded Gyhoeddus Mozilla yn rhoi'r hawl i chi ddosbarthu'r fersiwn rydych wedi ei newid.
+rights-intro-point-2 = Nid ydych yn derbyn unrhyw hawliau nod masnachu na thrwyddedau i nod masnach y Mozilla Foundation neu unrhyw barti, gan gynnwys y Mozzilla Foundation heb gyfyngiadau i enw na logo Firefox. Mae gwybodaeth bellach am nodau masnach i’w cael <a data-l10n-name="mozilla-trademarks-link">yma</a>.
+rights-intro-point-3 = Mae rhai nodweddion yn { -brand-short-name }, megis yr Adroddwr Chwalu, yn rhoi'r dewis i chi gyfrannu adborth i { -vendor-short-name }. Drwy ddewis cyflwyno adborth rydych yn rhoi i { -vendor-short-name } ganiatâd i ddefnyddio'r adborth i wella ei gynnyrch, i gyhoeddi'r adborth ar ei wefannau, ac i ddosbarthu'r adborth.
+rights-intro-point-4 = Mae sut rydym yn defnyddio y data personol ac adborth rydych wedi ei gyflwyno i { -vendor-short-name } drwy { -brand-short-name } yn cael ei ddisgrifio yn <a data-l10n-name="mozilla-privacy-policy-link">Polisi Preifatrwydd { -brand-short-name }</a>.
+rights-intro-point-4-unbranded = Rhaid rhestri unrhyw bolisïau preifatrwydd perthnasol yma.
+rights-intro-point-5 = Mae rhai nodweddion { -brand-short-name } yn gwneud defnydd p wasanaethau gwybodaeth gwe, er hynny nid ydym yn gallu gwarantu eu bod yn 100% yn gywir nac yn rhydd o wallau. Mae rhagor o fanylion, gan gynnwys gwybodaeth ar sut i'w hanalluogi i'w cael yn yr <a data-l10n-name="mozilla-service-terms-link">amodau gwasanaeth</a>.
+rights-intro-point-5-unbranded = Os yw'r cynnyrch yn cynnwys gwasanaethau gwe, rhaid cysylltu unrhyw amodau gwasanaeth perthnasol ar gyfer y gwasanaeth(au) i'r adran <a data-l10n-name="mozilla-website-services-link">Gwasanaethau Gwefan</a> Gwe.
+rights-intro-point-6 = Er mwyn chwarae rhai mathau o gynnwys fideo, mae { -brand-short-name } yn llwytho i lawr rhywfaint o gynnwys modiwlau dadgryptio gan drydydd partïon.
+rights-webservices-header = Gwasanaethau Gwybodaeth Gwe { -brand-full-name }
+rights-webservices = Mae { -brand-full-name } yn defnyddio gwasanaethau gwybodaeth gwe ("Gwasanaethau") i ddarparu rhai o'r nodweddion sy'n cael eu darparu ar eich cyfer yn y fersiwn yma o { -brand-short-name } o fewn yr amodau disgrifir isod. Os nad ydych am ddefnyddio un neu fwy o'r Gwasanaethau neu mae'r amodau yn annerbyniol, mae modd i chi analluogi'r nodwedd neu'r Gwasanaeth(au). Mae gwybodaeth ar sut i analluogi nodwedd neu Wasanaeth penodol i'w cael <a data-l10n-name="mozilla-disable-service-link">yma</a>. Mae modd analluogi nodweddion a Gwasanaethau eraill yn newisiadau'r rhaglen.
+rights-safebrowsing = <strong>Pori Diogel: </strong>Nid yw anablu Pori Diogel yn cael ei gymeradwyo gan y gall arwain i chi fynd i wefannau anniogel.  Os ydych eisiau analluogi'r nodwedd yn llwyr, dilynwch y camau hyn:
+rights-safebrowsing-term-1 = Agor dewisiadau'r rhaglen
+rights-safebrowsing-term-2 = Dewis Diogelwch
+rights-safebrowsing-term-3 = Dad dicio'r dewis i "{ enableSafeBrowsing-label }"
+enableSafeBrowsing-label = Rhwystro cynnwys peryglus a thwyllodrus
+rights-safebrowsing-term-4 = Mae Pori Diogel wedi ei analluogi
+rights-locationawarebrowsing = <strong>Pori Ymwybodol o Leoliad: </strong>yn ddewis i chi bob tro.  Ni fydd gwybodaeth yn cael ei anfon heb eich caniatâd.  Os hoffech chi analluogi'r nodwedd yn llwyr, dilynwch y camau hyn:
+rights-locationawarebrowsing-term-1 = Yn y bar URL, teipiwch <code>about:config</code>
+rights-locationawarebrowsing-term-2 = Teipio geo.enabled
+rights-locationawarebrowsing-term-3 = Clic dwbl i'r dewis geo.enabled
+rights-locationawarebrowsing-term-4 = Mae Pori Ymwybodol o Leoliad wedi ei analluogi
+rights-webservices-unbranded = Rhaid cynnwys yn fan hyn, drosolwg o'r gwasanaeth gwefan gwe mae'r cynnyrch yn ei gynnwys, ynghyd â chyfarwyddiadau ar sut i'w hatal os yn berthnasol.
+rights-webservices-term-unbranded = Rhaid rhestru amodau gwasanaethau gwe yma.
+rights-webservices-term-1 = Mae { -vendor-short-name } a'i gyfranwyr, trwyddedwyr, a phartneriaid yn gweithio i ddarparu'r Gwasanaethau mwyaf cywir a chyfredol.  Er hynny, nid oes modd i ni warantu fod y wybodaeth yn gynhwysfawr a diwall.  Er enghraifft, efallai na fydd y Gwasanaeth Pori Diogel yn adnabod rhai gwefannau anniogel ac efallai adnabod rhai gwefannau diogel ar gam. Mae pob lleoliad sy'n cael ei ddychwelyd gan ein darparwyr gwasanaeth ar gyfer y Gwasanaeth Ymwybodol o Leoliad yn amcanion yn unig. Nid ydym ni na'r darparwyr gwasanaeth yn gallu gwarantu cywirdeb y lleoliadau hyn.
+rights-webservices-term-2 = Gall { -vendor-short-name } atal neu newid y Gwasanaethau yn ôl eu mympwy.
+rights-webservices-term-3 = Mae croeso i chi ddefnyddio'r Gwasanaethau hyn gyda'r fersiwn yma o { -brand-short-name }, ac mae { -vendor-short-name } rhoi ei hawl i chi wneud hynny.  Mae { -vendor-short-name } a'i drwyddedwyr yn diogelu pob hawl arall yn y Gwasanaethau.  Nid yw'r amodau wedi eu hanelu at gyfyngu unrhyw hawliau o dan drwyddedau cod agored sy'n perthyn i { -brand-short-name } ac i'r fersiynau perthnasol o ffynonellau cod { -brand-short-name }.
+rights-webservices-term-4 = <strong>Mae'r gwasanaeth yn cael ei ddarparu "fel ag y mae".  Mae { -vendor-short-name }, ei gyfranwyr, trwyddedwyr, a dosbarthwyr, yn gwadu unrhyw warant, p'un ai yn cael ei fynegi neu ei awgrymu, gan gynnwys heb gyfyngiad, gwarant fod y Gwasanaethau yn farchnadadwy nac yn addas i'ch pwrpas penodol.  Rydych yn derbyn yr holl risg o ddewis y Gwasanaethau ar gyfer eich pwrpas ac i natur ansawdd a pherfformiad y Gwasanaeth. Nid yw rhai awdurdodau'n caniatáu eithrio neu gyfyngu gwarant sy'n cael ei awgrymu felly efallai nad yw'r gwadiad hwn yn berthnasol i chi.</strong>
+rights-webservices-term-5 = <strong>Yn wahanol i'r hyn sy'n angenrheidiol yn ôl y gyfraith, ni fydd { -vendor-short-name }, ei gyfranwyr, trwyddedwyr a dosbarthwyr yn agored i unrhyw iawndal anuniongyrchol, arbenigol, achlysurol, neu enghreifftiol yn codi o neu mewn unrhyw ffordd yn berthnasol i'r defnydd o { -brand-short-name } a'r Gwasanaethau.   Ni fydd yr atebolrwydd cyfunol o dan yr amodau hyn yn fwy na $500 (pum can dollar). Nid yw rhai awdurdodau yn caniatáu cyfyngu ar rhai materion difrod, felly efallai na fydd hyn yn berthnasol i chi.</strong>
+rights-webservices-term-6 = Gall { -vendor-short-name } ddiweddaru'r amodau yn ôl y galw o bryd i'w gilydd. Nid oes modd newid na dileu'r amodau heb ganiatâd ysgrifenedig { -vendor-short-name }.
+rights-webservices-term-7 = Mae'r amodau yn cael eu rheoli gan gyfreithiau talaith California, UDA, gan hepgor ei ddarpariaethau gwrthdaro cyfreithiol. Os yw unrhyw ran o'r amodau i'w cael heb rym cyfreithiol byd y gweddill yn sefyll mewn grym llawn ac effaith. Os digwydd gwrthdaro rhwng fersiwn sydd wedi ei gyfieithu a'r amodau hyn a'r fersiwn Saesneg, y fersiwn Saesneg fydd yn rheoli.
diff --git a/l10n-cy/toolkit/toolkit/about/aboutServiceWorkers.ftl b/l10n-cy/toolkit/toolkit/about/aboutServiceWorkers.ftl
new file mode 100644
index 0000000000..9474662afb
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/about/aboutServiceWorkers.ftl
@@ -0,0 +1,40 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+### The term "Service Workers" and "Workers" should not be translated
+
+about-service-workers-title = Ynghylch Service Workers
+about-service-workers-main-title = Service Workers Cofrestredig
+about-service-workers-warning-not-enabled = Nid yw Service Workers wedi eu galluogi.
+about-service-workers-warning-no-service-workers = Does dim Service Workers wedi eu cofrestru.
+
+# The original title of service workers' information
+#
+# Variables:
+#   $originTitle: original title
+origin-title = Tarddiad: { $originTitle }
+
+## These strings are for showing the information of workers.
+##
+## Variables:
+##  $name: the name of scope, active cache, waiting cache and the push end point.
+##  $url: the url of script specification and current worker.
+
+scope = <strong>Ystod:</strong> { $name }
+script-spec = <strong>Manyleb Sgript:</strong> <a data-l10n-name="link">{ $url }</a>
+current-worker-url = <strong>URL Worker Cyfredol:</strong> <a data-l10n-name="link">{ $url }</a>
+active-cache-name = <strong>Enw'r Storfa Dros Dro Weithredol:</strong> { $name }
+waiting-cache-name = <strong>Enw'r Storfa Dros Dro sy'n Aros:</strong> { $name }
+push-end-point-waiting = <strong>Push Endpoint:</strong> { waiting }
+push-end-point-result = <strong>Push Endpoint:</strong> { $name }
+
+# This term is used as a button label (verb, not noun).
+update-button = Diweddaru
+
+unregister-button = Dadgofrestru
+
+unregister-error = Methwyd dadgofrestru'r Service Workers.
+
+waiting = Aros…
diff --git a/l10n-cy/toolkit/toolkit/about/aboutSupport.ftl b/l10n-cy/toolkit/toolkit/about/aboutSupport.ftl
new file mode 100644
index 0000000000..330dab3812
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/about/aboutSupport.ftl
@@ -0,0 +1,425 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+page-title = Gwybodaeth am Ddatrys Problemau
+page-subtitle = Mae'r dudalen hon yn cynnwys gwybodaeth dechnegol a allai fod yn ddefnyddiol pan fyddwch yn ceisio datrys problem. Os ydych yn chwilio am atebion i gwestiynau cyffredin am { -brand-short-name }, edrychwch ar ein <a data-l10n-name="support-link">gwefan cefnogaeth</a>.
+crashes-title = Ardroddiad Chwalu
+crashes-id = Enw'r Adroddiad
+crashes-send-date = Cyflwynwyd
+crashes-all-reports = Pob Adroddiad Chwalu
+crashes-no-config = Mae'r rhaglen wedi ei ffurfweddu i ddangos adroddiadau chwalu.
+extensions-title = Estyniadau
+extensions-name = Enw
+extensions-enabled = Galluogwyd
+extensions-version = Fersiwn
+extensions-id = ID
+support-addons-title = Ychwanegion
+support-addons-name = Enw
+support-addons-type = Math
+support-addons-enabled = Galluogwyd
+support-addons-version = Fersiwn
+support-addons-id = ID
+security-software-title = Meddalwedd Diogelwch
+security-software-type = Math
+security-software-name = Enw
+security-software-antivirus = Gwrth Firws
+security-software-antispyware = Gwrthysbiwar
+security-software-firewall = Mur Cadarn
+features-title = Nodweddion { -brand-short-name }
+features-name = Enw
+features-version = Fersiwn
+features-id = ID
+processes-title = Prosesau Pell
+processes-type = Math
+processes-count = Cyfrif
+app-basics-title = Sylfaeni Rhaglen
+app-basics-name = Enw
+app-basics-version = Fersiwn
+app-basics-build-id = Cyfeirnod Adeiladu
+app-basics-distribution-id = ID Dosbarthu
+app-basics-update-channel = Sianel Diweddaru
+# This message refers to the folder used to store updates on the device,
+# as in "Folder for updates". "Update" is a noun, not a verb.
+app-basics-update-dir =
+    { PLATFORM() ->
+        [linux] Diweddaru Cyfeiriadur
+       *[other] Diweddaru Ffolder
+    }
+app-basics-update-history = Hanes Diweddaru
+app-basics-show-update-history = Dangos Hanes Diweddaru
+# Represents the path to the binary used to start the application.
+app-basics-binary = Deuaidd y Rhaglen
+app-basics-profile-dir =
+    { PLATFORM() ->
+        [linux] Cyfeiriadur Proffil
+       *[other] Ffolder Proffil
+    }
+app-basics-enabled-plugins = Ategion Galluogwyd
+app-basics-build-config = Ffurfweddiad Adeiladu
+app-basics-user-agent = Asiant Defnyddiwr
+app-basics-os = SW
+# Rosetta is Apple's translation process to run apps containing x86_64
+# instructions on Apple Silicon. This should remain in English.
+app-basics-rosetta = Cyfieithu gan Rosetta
+app-basics-memory-use = Defnydd o'r cof
+app-basics-performance = Perfformiad
+app-basics-service-workers = Service Workers Cofrestredig
+app-basics-profiles = Proffiliau
+app-basics-launcher-process-status = Proses Lansio
+app-basics-multi-process-support = Ffenestri Amlbroses
+app-basics-fission-support = Ffenestri Fission
+app-basics-remote-processes-count = Prosesau Pell
+app-basics-enterprise-policies = Polisïau Mentrau
+app-basics-location-service-key-google = Allwedd Google Location Service
+app-basics-safebrowsing-key-google = Allwedd Google Safebrowsing
+app-basics-key-mozilla = Mozilla Location Service Key
+app-basics-safe-mode = Modd Diogel
+show-dir-label =
+    { PLATFORM() ->
+        [macos] Dangos yn Finder
+        [windows] Agor Ffolder
+       *[other] Agor Cyfeiriadur
+    }
+environment-variables-title = Newidiolion Amgylcheddol
+environment-variables-name = Enw
+environment-variables-value = Gwerth
+experimental-features-title = Nodweddion Arbrofol
+experimental-features-name = Enw
+experimental-features-value = Gwerth
+modified-key-prefs-title = Dewisiadau Pwysig wedi eu Newid
+modified-prefs-name = Enw
+modified-prefs-value = Gwerth
+user-js-title = Dewisiadau user.js
+user-js-description = Mae eich ffolder profil yn cynnwys <a data-l10n-name="user-js-link">ffeil user.js</a>, sy'n cynnwys dewisiadau sydd heb eu creu gan { -brand-short-name }.
+locked-key-prefs-title = Dewisiadau Pwysig Wedi eu Cloi
+locked-prefs-name = Enw
+locked-prefs-value = Gwerth
+graphics-title = Graffigau
+graphics-features-title = Nodweddion
+graphics-diagnostics-title = Diagnosteg
+graphics-failure-log-title = Cofnod Methiant
+graphics-gpu1-title = GPU #1
+graphics-gpu2-title = GPU #2
+graphics-decision-log-title = Cofnod Penderfynnu
+graphics-crash-guards-title = Nodweddion Crash Guard wedi ei Analluogi
+graphics-workarounds-title = Dulliau Datrys
+# Windowing system in use on Linux (e.g. X11, Wayland).
+graphics-window-protocol = Protocol Ffenestr
+# Desktop environment in use on Linux (e.g. GNOME, KDE, XFCE, etc).
+graphics-desktop-environment = Amgylchedd Bwrdd Gwaith
+place-database-title = Cronfa Ddata Mannau
+place-database-integrity = Cyfanrwydd
+place-database-verify-integrity = Gwirio Cyfanrwydd
+a11y-title = Hygyrchedd
+a11y-activated = Gweithredu
+a11y-force-disabled = Atal Hygyrchedd
+a11y-handler-used = Defnyddiwyd Trinydd Mynediadwy
+a11y-instantiator = Enghreifftiad Hygyrchedd
+library-version-title = Fersiynau Llyfrgell
+copy-text-to-clipboard-label = Copïo testun i'r clipfwrdd
+copy-raw-data-to-clipboard-label = Copïo data bras i'r clipfwrdd
+sandbox-title = Blwch tywod
+sandbox-sys-call-log-title = Galwadau System wedi eu Gwrthod
+sandbox-sys-call-index = #
+sandbox-sys-call-age = Eiliad yn Ôl
+sandbox-sys-call-pid = PID
+sandbox-sys-call-tid = TID
+sandbox-sys-call-proc-type = Math o Brosesu
+sandbox-sys-call-number = Syscall
+sandbox-sys-call-args = Ymresymiadau
+safe-mode-title = Defnyddiwch y Modd Diogel
+restart-in-safe-mode-label = Ailgychwyn gydag Ychwanegion wedi eu Hanalluogi…
+clear-startup-cache-title = Ceisiwch glirio'r storfa gychwyn
+clear-startup-cache-label = Clirio'r storfa gychwyn…
+startup-cache-dialog-title = Clirio'r storfa gychwyn
+startup-cache-dialog-body = Ailgychwyn { -brand-short-name } i glirio storfa cychwyn. Ni fydd hyn yn newid eich gosodiadau nac yn dileu estyniadau rydych chi wedi'u hychwanegu at { -brand-short-name }.
+restart-button-label = Ailgychwyn
+
+## Media titles
+
+audio-backend = Cefn Sain
+max-audio-channels = Mwyaf o Sianeli
+sample-rate = Graddfa Samplo Amgen
+roundtrip-latency = Cylchdro cudd (gwyriad safonol)
+media-title = Cyfrwng
+media-output-devices-title = Dyfeisiau Allbwn
+media-input-devices-title = Dyfeisiau Mewnbwn
+media-device-name = Enw
+media-device-group = Grŵp
+media-device-vendor = Gwerthwr
+media-device-state = Cyflwr
+media-device-preferred = Amgen
+media-device-format = Fformat
+media-device-channels = Sianeli
+media-device-rate = Cyfradd
+media-device-latency = Cuddni
+media-capabilities-title = Gallu Cyfryngol
+# List all the entries of the database.
+media-capabilities-enumerate = Cyfrifo'r gronfa ddata
+
+##
+
+intl-title = Rhyngwladoli a Lleoleiddio
+intl-app-title = Gosodiadau'r Rhaglen
+intl-locales-requested = Locales Gofynnwyd Amdanynt
+intl-locales-available = Locales ar Gael
+intl-locales-supported = Locales Apiau
+intl-locales-default = Locale Rhagosodedig
+intl-os-title = System Weithredu
+intl-os-prefs-system-locales = Locales y System
+intl-regional-prefs = Dewisiadau Rhanbarthol
+
+## Remote Debugging
+##
+## The Firefox remote protocol provides low-level debugging interfaces
+## used to inspect state and control execution of documents,
+## browser instrumentation, user interaction simulation,
+## and for subscribing to browser-internal events.
+##
+## See also https://firefox-source-docs.mozilla.org/remote/
+
+remote-debugging-title = Dadfygio o Bell (Protocol Cromiwm)
+remote-debugging-accepting-connections = Derbyn Cysylltiadau
+remote-debugging-url = URL
+
+##
+
+support-third-party-modules-title = Modiwlau Trydydd Parti
+support-third-party-modules-module = Ffeil Modiwlau
+support-third-party-modules-version = Fersiwn Ffeil
+support-third-party-modules-vendor = Manylion y Gwerthwr
+support-third-party-modules-occurrence = Amlder
+support-third-party-modules-process = Math o Broses ac ID
+support-third-party-modules-thread = Trywydd
+support-third-party-modules-base = Cyfeiriad Imagebase
+support-third-party-modules-uptime = Cyfnod Proses (me)
+support-third-party-modules-duration = Cyfnod Llwytho (me)
+support-third-party-modules-status = Statws
+support-third-party-modules-status-loaded = Wedi llwytho
+support-third-party-modules-status-blocked = Wedi Rhwystro
+support-third-party-modules-status-redirected = Wedi Ailgyfeirio
+support-third-party-modules-empty = Heb lwytho unrhyw fodiwlau trydydd parti.
+support-third-party-modules-no-value = (Dim gwerth)
+support-third-party-modules-button-open =
+    .title = Lleoliad ffeil agored...
+support-third-party-modules-expand =
+    .title = Dangos gwybodaeth fanwl
+support-third-party-modules-collapse =
+    .title = Cau gwybodaeth fanwl
+support-third-party-modules-unsigned-icon =
+    .title = Nid yw'r modiwl hwn wedi'i lofnodi
+support-third-party-modules-folder-icon =
+    .title = Lleoliad ffeil agored...
+support-third-party-modules-down-icon =
+    .title = Dangos gwybodaeth fanwl
+support-third-party-modules-up-icon =
+    .title = Cau gwybodaeth fanwl
+# Variables
+# $days (Integer) - Number of days of crashes to log
+report-crash-for-days =
+    { $days ->
+        [zero] Ni fu Adroddiadau Chwalu
+        [one] Adroddiadau Chwalu'r { $days } Diwrnod Diwethaf
+        [two] Adroddiadau Chwalu'r { $days } Ddiwrnod Diwethaf
+        [few] Adroddiadau Chwalu'r { $days } Diwrnod Diwethaf
+        [many] Adroddiadau chwalu'r { $days } Diwrnod Diwethaf
+       *[other] Adroddiadau chwalu'r { $days } Diwrnod Diwethaf
+    }
+# Variables
+# $minutes (integer) - Number of minutes since crash
+crashes-time-minutes =
+    { $minutes ->
+        [zero] Dim munudau yn ôl
+        [one] { $minutes } munud yn ôl
+        [two] { $minutes } funud yn ôl
+        [few] { $minutes } munud yn ôl
+        [many] { $minutes } munud yn ôl
+       *[other] { $minutes } munud yn ôl
+    }
+# Variables
+# $hours (integer) - Number of hours since crash
+crashes-time-hours =
+    { $hours ->
+        [zero] Dim oriau yn ôl
+        [one] { $hours } awr yn ôl
+        [two] { $hours } awr yn ôl
+        [few] { $hours } awr yn ôl
+        [many] { $hours } awr yn ôl
+       *[other] { $hours } awr yn ôl
+    }
+# Variables
+# $days (integer) - Number of days since crash
+crashes-time-days =
+    { $days ->
+        [zero] Dim dyddiau yn ôl
+        [one] { $days } diwrnod yn ôl
+        [two] { $days } ddiwrnod yn ôl
+        [few] { $days } diwrnod yn ôl
+        [many] { $days } diwrnod yn ôl
+       *[other] { $days } diwrnod yn ôl
+    }
+# Variables
+# $reports (integer) - Number of pending reports
+pending-reports =
+    { $reports ->
+        [zero] Dim Adroddiadau Chwalu
+        [one] Pob Adroddiad Chwalu (gan gynnwys { $reports } chwalfa disgwyliedig o fewn ystod penodol o amser)
+        [two] Pob Adroddiad Chwalu (gan gynnwys { $reports } chwalfa disgwyliedig o fewn ystod penodol o amser)
+        [few] Pob Adroddiad Chwalu (gan gynnwys { $reports } chwalfa disgwyliedig o fewn ystod penodol o amser)
+        [many] Pob Adroddiad Chwalu (gan gynnwys { $reports } chwalfa disgwyliedig o fewn ystod penodol o amser)
+       *[other] Pob Adroddiad Chwalu (gan gynnwys { $reports } chwalfa disgwyliedig o fewn ystod penodol o amser)
+    }
+raw-data-copied = Copïwyd data bras i'r clipfwrdd
+text-copied = Copïwyd testun i'r clipfwrdd
+
+## The verb "blocked" here refers to a graphics feature such as "Direct2D" or "OpenGL layers".
+
+blocked-driver = Wedi ei rwystro ar gyfer y fersiwn o'ch gyrrwr graffigol chi.
+blocked-gfx-card = Wedi ei rwystro ar gyfer eich cerdyn graffigol oherwydd pryderon gyrrwr heb eu datrys.
+blocked-os-version = Wedi ei rwystro ar gyfer eich fersiwn chi o'r system weithredu.
+blocked-mismatched-version = Rhwystro ar gyfer gwrthdaro fersiwn gyrrwr graffig y gofrestrfa a'r DLL.
+# Variables
+# $driverVersion - The graphics driver version string
+try-newer-driver = Wedi ei rwystro ar gyfer eich gyrrwr graffigol chi. Ceisiwch ddiweddaru'r gyrrwr i fersiwn { $driverVersion } neu ddiweddarach.
+# "ClearType" is a proper noun and should not be translated. Feel free to leave English strings if
+# there are no good translations, these are only used in about:support
+clear-type-parameters = Paramedrau ClearType
+compositing = Cyfosod
+hardware-h264 = Dadgodio Caledwedd H264
+main-thread-no-omtc = prif drywydd, dim OMTC
+yes = Iawn
+no = Na
+unknown = Anhysbys
+virtual-monitor-disp = Dangosiad Monitor Rhithwir
+
+## The following strings indicate if an API key has been found.
+## In some development versions, it's expected for some API keys that they are
+## not found.
+
+found = Wedi Canfod
+missing = Coll
+gpu-process-pid = GPUProcessPid
+gpu-process = GPUProcess
+gpu-description = Disgrifiad
+gpu-vendor-id = Enw'r Gwerthwr
+gpu-device-id = Enw Dyfais
+gpu-subsys-id = Enw subsys
+gpu-drivers = Gyrwyr
+gpu-ram = RAM
+gpu-driver-vendor = Gwerthwr Gyrwyr
+gpu-driver-version = Fersiwn Gyrrwr
+gpu-driver-date = Dyddiad y Gyrrwr
+gpu-active = Gweithredol
+webgl1-wsiinfo = Gwybodaeth WSI ar yrrwr WebGL 1
+webgl1-renderer = Rendrwr Gyrrwr WebGL 1
+webgl1-version = Fersiwn Gyrrwr WebGL 1
+webgl1-driver-extensions = Estyniadau Gyrrwr WebGL 1
+webgl1-extensions = Estyniadau WebGL 1
+webgl2-wsiinfo = Gwybodaeth WSI Gyrrwr WebGL 2
+webgl2-renderer = Rendrwr Gyrrwr WebGL 2
+webgl2-version = Fersiwn Gyrrwr WebGL 2
+webgl2-driver-extensions = Estyniadau Gyrrwr WebGL 2
+webgl2-extensions = Estyniadau WebGL 2
+blocklisted-bug = Wedi eu rhwystro ar sail gwybodaeth hysbys
+# Variables
+# $bugNumber (string) - String of bug number from Bugzilla
+bug-link = gwall { $bugNumber }
+# Variables
+#   $bugNumber (string) - Bug number on Bugzilla
+support-blocklisted-bug = Ar y Rhestr Rhwystro oherwydd materion hysbys: <a data-l10n-name="bug-link">bug { $bugNumber }</a>
+# Variables
+# $failureCode (string) - String that can be searched in the source tree.
+unknown-failure = Wedi ei rwystro; gwall cod { $failureCode }
+d3d11layers-crash-guard = Cyfosodwr D3D11
+d3d11video-crash-guard = Dadgodiwr Fideo D3D11
+d3d9video-crash-guard = Dadgodiwr Fideo D3D9
+glcontext-crash-guard = OpenGL
+wmfvpxvideo-crash-guard = Dadgodiwr Fideo WMF VPX
+reset-on-next-restart = Ailosod wrth Ailgychwyn
+gpu-process-kill-button = Gorffen Proses GPU
+gpu-device-reset = Ailosod Dyfais
+gpu-device-reset-button = Ailosod Dyfais Trigro
+uses-tiling = Yn defnyddio Teilsio
+content-uses-tiling = Yn Defnyddio Teilsio (Cynnwys)
+off-main-thread-paint-enabled = Galluogwyd Paentio All Brif Drywydd
+off-main-thread-paint-worker-count = Cyfrif Gweithiwr Paentio Oddi ar y Brif Drywydd
+target-frame-rate = Graddfa Ffrâm Darged
+min-lib-versions = Fersiwn lleiaf disgwyliedig
+loaded-lib-versions = Fersiwn mewn defnydd
+has-seccomp-bpf = Seccomp-BPF (Hidlo Galw System)
+has-seccomp-tsync = Cydweddiad Edafedd Seccomp
+has-user-namespaces = Bylchau Enwau Defnyddiwr
+has-privileged-user-namespaces = Bylchau Enw Defnyddiwr fel prosesau breintiedig
+can-sandbox-content = Blwch Tywod Proses Cynnwys
+can-sandbox-media = Blwch Tywod Ategyn Cyfrwng
+content-sandbox-level = Lefel Blwch Tywod Proses Cynnwys
+effective-content-sandbox-level = Lefel Blwch Tywod Proses Cynnwys Effeithiol
+sandbox-proc-type-content = cynnwys
+sandbox-proc-type-file = cynnwys ffeil
+sandbox-proc-type-media-plugin = ategyn cyfrwng
+sandbox-proc-type-data-decoder = datgodydd data
+startup-cache-title = Storfa cychwyn
+startup-cache-disk-cache-path = Llwybr Storfa Disg
+startup-cache-ignore-disk-cache = Anwybyddu Storfa Disg
+startup-cache-found-disk-cache-on-init = Wedi dod o hyd i Storfa Disg ar Init
+startup-cache-wrote-to-disk-cache = Ysgrifennwyd at Storfa Disg
+launcher-process-status-0 = Galluogwyd
+launcher-process-status-1 = Analluogwyd oherwydd methiant
+launcher-process-status-2 = Analluogwyd yn orfodol
+launcher-process-status-unknown = Statws anhysbys
+# Variables
+# $remoteWindows (integer) - Number of remote windows
+# $totalWindows (integer) - Number of total windows
+multi-process-windows = { $remoteWindows }/{ $totalWindows }
+multi-process-status-0 = Galluogwyd gan y defnyddiwr
+multi-process-status-1 = Galluogwyd drwy ragosodiad
+multi-process-status-2 = Analluogwyd
+multi-process-status-4 = Analluogwyd gan offer hygyrchedd
+multi-process-status-6 = Analluogwyd gan fewnbwn testun heb ei gynnal
+multi-process-status-7 = Analluogwyd gan ychwanegion
+multi-process-status-8 = Analluogi gorfodol
+multi-process-status-unknown = Statws anhysbys
+# Variables
+# $fissionWindows (integer) - Number of remote windows
+# $totalWindows (integer) - Number of total windows
+fission-windows = { $fissionWindows }/{ $totalWindows }
+fission-status-experiment-control = Analluogwyd trwy arbrawf
+fission-status-experiment-treatment = Galluogwyd trwy arbrawf
+fission-status-disabled-by-e10s-env = Analluogwyd gan yr amgylchedd
+fission-status-enabled-by-env = Galluogwyd gan yr amgylchedd
+fission-status-disabled-by-safe-mode = Analluogwyd gan y modd diogel
+fission-status-enabled-by-default = Galluogwyd drwy ragosodiad
+fission-status-disabled-by-default = Analluogwyd drwy ragosodiad
+fission-status-enabled-by-user-pref = Galluogwyd gan y defnyddiwr
+fission-status-disabled-by-user-pref = Analluogwyd gan y defnyddiwr
+fission-status-disabled-by-e10s-other = E10s wedi ei analluogi
+async-pan-zoom = Chwyddo a Thremio Anghydamseredig
+apz-none = dim
+wheel-enabled = mewnbwn olwyn wedi ei alluogi
+touch-enabled = mewnbwn cyffwrdd wedi ei alluogi
+drag-enabled = wedi galluogu llusgo bar sgrolio
+keyboard-enabled = bysellfwrdd wedi ei anlluogi
+autoscroll-enabled = galluogwyd awtosgrolio
+zooming-enabled = pinsio chwyddo llyfn wedi'i alluogi
+
+## Variables
+## $preferenceKey (string) - String ID of preference
+
+wheel-warning = Mae mewnbwn olwyn async wedi ei analluogi oherwydd diffyg cefnogaeth pref: { $preferenceKey }
+touch-warning = Mae mewnbwn cyffwrdd async wedi ei analluogi oherwydd diffyg cefnogaeth pref: { $preferenceKey }
+
+## Strings representing the status of the Enterprise Policies engine.
+
+policies-inactive = Anweithredol
+policies-active = Gweithredol
+policies-error = Gwall
+
+## Printing section
+
+support-printing-title = Yn argraffu
+support-printing-troubleshoot = Datrys Anawsterau
+support-printing-clear-settings-button = Clirio gosodiadau argraffu wedi'u cadw
+support-printing-modified-settings = Gosodiadau argraffu wedi'u haddasu
+support-printing-prefs-name = Enw
+support-printing-prefs-value = Gwerth
diff --git a/l10n-cy/toolkit/toolkit/about/aboutTelemetry.ftl b/l10n-cy/toolkit/toolkit/about/aboutTelemetry.ftl
new file mode 100644
index 0000000000..4766c6b2af
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/about/aboutTelemetry.ftl
@@ -0,0 +1,151 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+about-telemetry-ping-data-source = Ffynhonnell data ping:
+about-telemetry-show-current-data = Data cyfredol
+about-telemetry-show-archived-ping-data = Data ping wedi ei archifo
+about-telemetry-show-subsession-data = Dangos data is-sesiwn
+about-telemetry-choose-ping = Dewis ping:
+about-telemetry-archive-ping-type = Math Ping
+about-telemetry-archive-ping-header = Ping
+about-telemetry-option-group-today = Heddiw
+about-telemetry-option-group-yesterday = Ddoe
+about-telemetry-option-group-older = Hŷn
+about-telemetry-previous-ping = <<
+about-telemetry-next-ping = >>
+about-telemetry-page-title = Data Telemetreg
+about-telemetry-current-store = Storfa Gyfredol:
+about-telemetry-more-information = Chwilio am ragor o wybodaeth?
+about-telemetry-firefox-data-doc = Mae'r <a data-l10n-name="data-doc-link">Firefox Data Documentation</a> yn cynnwys canllawiau ar sut i weithio gyda'n offer data.
+about-telemetry-telemetry-client-doc = Mae <a data-l10n-name="client-doc-link">dogfennaeth cleient Firefox Telemetry</a> yn cynnwys diffiniadau o gysyniadau, dogfennaeth API a chyfeiriadau data.
+about-telemetry-telemetry-dashboard = Mae <a data-l10n-name="dashboard-link">byrddau gwaith Telemetreg</a> yn caniatáu i chi weld y data mae Mozilla yn ei dderbyn drwy'r Delemetreg.
+about-telemetry-telemetry-probe-dictionary = Mae'r <a data-l10n-name="probe-dictionary-link">Geiriadur Archwilio</a> yn darparu manylion a disgrifiadau ar gyfer y chwilio gasglwyd gan Delemetreg.
+about-telemetry-show-in-Firefox-json-viewer = Agor yn y darllenydd JSON
+about-telemetry-home-section = Cartref
+about-telemetry-general-data-section = Data Cyffredinol
+about-telemetry-environment-data-section = Data'r Amgylchedd
+about-telemetry-session-info-section = Manylion Sesiwn
+about-telemetry-scalar-section = Scalarau
+about-telemetry-keyed-scalar-section = Graddfeydd Allweddedig
+about-telemetry-histograms-section = Histogramau
+about-telemetry-keyed-histogram-section = Histogramau Allweddol
+about-telemetry-events-section = Digwyddiadau
+about-telemetry-simple-measurements-section = Mesuriadau Syml
+about-telemetry-slow-sql-section = Datganiadau SQL Araf
+about-telemetry-addon-details-section = Manylion Ychwanegyn
+about-telemetry-captured-stacks-section = Staciau wedi eu Cipio
+about-telemetry-late-writes-section = Ysgrifennu Hwyr
+about-telemetry-raw-payload-section = Llwyth Bras
+about-telemetry-raw = JSON bras
+about-telemetry-full-sql-warning = SYLW: Mae dadfygio SQL araf wedi ei alluogi. Gall llinynnau SQL llawn gael eu dangos isod ond ni fyddant yn cael eu trosglwyddo i'r Telemetreg.
+about-telemetry-fetch-stack-symbols = Estyn enwau swyddogaethau ar gyfer pentyrrau
+about-telemetry-hide-stack-symbols = Dangos data pentwr bras
+# Selects the correct release version
+# Variables:
+#   $channel (String): represents the corresponding release data string
+about-telemetry-data-type =
+    { $channel ->
+        [release] ryddhau data
+       *[prerelease] data cyn ryddhau
+    }
+# Selects the correct upload string
+# Variables:
+#   $uploadcase (String): represents a corresponding upload string
+about-telemetry-upload-type =
+    { $uploadcase ->
+        [enabled] galluogwyd
+       *[disabled] analluogwyd
+    }
+# Example Output: 1 sample, average = 0, sum = 0
+# Variables:
+#   $sampleCount (Integer): amount of histogram samples
+#   $prettyAverage (Integer): average of histogram samples
+#   $sum (Integer): sum of histogram samples
+about-telemetry-histogram-stats =
+    { $sampleCount ->
+        [zero] { $sampleCount } sampl, cyfartaledd= { $prettyAverage }, swm = { $sum }
+        [one] { $sampleCount } sampl, cyfartaledd= { $prettyAverage }, swm = { $sum }
+        [two] { $sampleCount } sampl, cyfartaledd= { $prettyAverage }, swm = { $sum }
+        [few] { $sampleCount } sampl, cyfartaledd= { $prettyAverage }, swm = { $sum }
+        [many] { $sampleCount } sampl, cyfartaledd= { $prettyAverage }, swm = { $sum }
+       *[other] { $sampleCount } sampl, cyfartaledd= { $prettyAverage }, swm = { $sum }
+    }
+# Variables:
+#   $telemetryServerOwner (String): the value of the toolkit.telemetry.server_owner preference. Typically "Mozilla"
+about-telemetry-page-subtitle = Mae'r dudalen hon yn dangos gwybodaeth am berfformiad, caledwedd, defnydd a chyfaddasiadau a gasglwyd gan y Delemetreg. Mae'r wybodaeth yn cael ei gyflwyno i { $telemetryServerOwner } er mwyn gwella { -brand-full-name }.
+about-telemetry-settings-explanation = Mae telemetreg yn casglu { about-telemetry-data-type } a'r llwyth yw <a data-l10n-name="upload-link">{ about-telemetry-upload-type }</a>.
+# Variables:
+#   $name (String): ping name, e.g. “saved-session”
+#   $timeStamp (String): ping localized timestamp, e.g. “2017/07/08 10:40:46”
+about-telemetry-ping-details = Mae pob darn o wybodaeth wedi ei anfon wedi ei becynnu i “<a data-l10n-name="ping-link">pingiau</a>”. Rydych yn edrych ar ping { $name }, { $timestamp }.
+about-telemetry-data-details-current = Mae pob darn o wybodaeth yn cael ei anfon wedi'i fwndelu i “<a data-l10n-name="ping-link">bingiadau</a>“. Rydych yn edrych ar y data cyfredol.
+# string used as a placeholder for the search field
+# More info about it can be found here:
+# https://firefox-source-docs.mozilla.org/toolkit/components/telemetry/telemetry/data/main-ping.html
+# Variables:
+#   $selectedTitle (String): the section name from the structure of the ping.
+about-telemetry-filter-placeholder =
+    .placeholder = Canfod yn y { $selectedTitle }
+about-telemetry-filter-all-placeholder =
+    .placeholder = Canfod ym mhob adran
+# Variables:
+#   $searchTerms (String): the searched terms
+about-telemetry-results-for-search = Canlyniadau “{ $searchTerms }”
+# More info about it can be found here: https://firefox-source-docs.mozilla.org/toolkit/components/telemetry/telemetry/data/main-ping.html
+# Variables:
+#   $sectionName (String): the section name from the structure of the ping.
+#   $currentSearchText (String): the current text in the search input
+about-telemetry-no-search-results = Ymddiheuriadau! Does dim canlyniadau yn { $sectionName } ar gyfer “{ $currentSearchText }”
+# Variables:
+#   $searchTerms (String): the searched terms
+about-telemetry-no-search-results-all = Ymddiheuriadau! Nid oes canlyniadau i unrhyw adran am “{ $searchTerms }”
+# This message is displayed when a section is empty.
+# Variables:
+#   $sectionName (String): is replaced by the section name.
+about-telemetry-no-data-to-display = Ymddiheuriadau! Nid oes data ar gael ar hyn o bryd yn “{ $sectionName }”
+# used as a tooltip for the “current” ping title in the sidebar
+about-telemetry-current-data-sidebar = data cyfredol
+# used in the “Ping Type” select
+about-telemetry-telemetry-ping-type-all = popeth
+# button label to copy the histogram
+about-telemetry-histogram-copy = Copïo
+# these strings are used in the “Slow SQL Statements” section
+about-telemetry-slow-sql-main = Datganiadau SQL Araf ar y Prif Drywydd
+about-telemetry-slow-sql-other = Datganiadau SQL Araf ar y Trywyddion Cynorthwyol
+about-telemetry-slow-sql-hits = Trawiadau
+about-telemetry-slow-sql-average = Amser Cyfartalog (ms)
+about-telemetry-slow-sql-statement = Datganiad
+# these strings are used in the “Add-on Details” section
+about-telemetry-addon-table-id = Enw'r Ychwanegyn
+about-telemetry-addon-table-details = Manylion
+# Variables:
+#   $addonProvider (String): the name of an Add-on Provider (e.g. “XPI”, “Plugin”)
+about-telemetry-addon-provider = Darparwr { $addonProvider }
+about-telemetry-keys-header = Priodwedd
+about-telemetry-names-header = Enw
+about-telemetry-values-header = Gwerth
+# Variables:
+#   $stackKey (String): the string key for this stack
+#   $capturedStacksCount (Integer):  the number of times this stack was captured
+about-telemetry-captured-stacks-title = { $stackKey } (cyfrif cipio: { $capturedStacksCount })
+# Variables:
+#   $lateWriteCount (Integer): the number of the late writes
+about-telemetry-late-writes-title = Ysgrifennu Hwyr #{ $lateWriteCount }
+about-telemetry-stack-title = Stac:
+about-telemetry-memory-map-title = Map cof:
+about-telemetry-error-fetching-symbols = Digwyddodd gwall wrth estyn symbolau. Gwiriwch eich bod wedi eich cysylltu â'r rhyngrwyd a cheisio eto.
+about-telemetry-time-stamp-header = stamp amser
+about-telemetry-category-header = categori
+about-telemetry-method-header = dull
+about-telemetry-object-header = gwrthrych
+about-telemetry-extra-header = ychwanegol
+about-telemetry-origin-section = Telemetreg y Tarddiad
+about-telemetry-origin-origin = tarddiad
+about-telemetry-origin-count = cyfrif
+# Variables:
+#   $telemetryServerOwner (String): the value of the toolkit.telemetry.server_owner preference. Typically "Mozilla"
+about-telemetry-origins-explanation = Mae <a data-l10n-name="origin-doc-link">Firefox Origin Telemetry</a> yn amgodio data cyn iddo gael ei anfon fel bod { $telemetryServerOwner } yn gallu cyfrif pethau, ond heb wybod a yw { -brand-product-name } wedi cyfrannu i'r cyfrif hwnnw. (<a data-l10n-name="prio-blog-link">Dysgu rhagor</a>)
+# Variables:
+#  $process (String): type of process in subsection headers ( e.g. "content", "parent" )
+about-telemetry-process = Proses { $process }
diff --git a/l10n-cy/toolkit/toolkit/about/aboutWebrtc.ftl b/l10n-cy/toolkit/toolkit/about/aboutWebrtc.ftl
new file mode 100644
index 0000000000..8cedc061c8
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/about/aboutWebrtc.ftl
@@ -0,0 +1,255 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+### Localization for about:webrtc, a troubleshooting and diagnostic page
+### for WebRTC calls. See https://developer.mozilla.org/en-US/docs/Web/API/WebRTC_API.
+
+# The text "WebRTC" is a proper noun and should not be translated.
+about-webrtc-document-title = Materion Mewnol WebRTC
+# "about:webrtc" is a internal browser URL and should not be
+# translated. This string is used as a title for a file save dialog box.
+about-webrtc-save-page-dialog-title = cadw about:webrtc fel
+
+## AEC is an abbreviation for Acoustic Echo Cancellation.
+
+about-webrtc-aec-logging-msg-label = Cofnodi AEC
+about-webrtc-aec-logging-off-state-label = Cychwyn Cofnodi AEC
+about-webrtc-aec-logging-on-state-label = Atal Cofnodi AEC
+about-webrtc-aec-logging-on-state-msg = Cofnodi AEC yn weithredol (siarad gyda'r galwr am ychydig funudau ac yna atal y cipio)
+
+##
+
+# "PeerConnection" is a proper noun associated with the WebRTC module. "ID" is
+# an abbreviation for Identifier. This string should not normally be translated
+# and is used as a data label.
+about-webrtc-peerconnection-id-label = Dynodiad PeerConnection:
+
+## "SDP" is an abbreviation for Session Description Protocol, an IETF standard.
+## See http://wikipedia.org/wiki/Session_Description_Protocol
+
+about-webrtc-sdp-heading = SDP
+about-webrtc-local-sdp-heading = SDP lleol
+about-webrtc-local-sdp-heading-offer = SDP lleol (Cynnig)
+about-webrtc-local-sdp-heading-answer = SDP lleol (Ateb)
+about-webrtc-remote-sdp-heading = SDP pell
+about-webrtc-remote-sdp-heading-offer = SDP pell (Cynnig)
+about-webrtc-remote-sdp-heading-answer = SDP pell (Ateb)
+about-webrtc-sdp-history-heading = Hanes SDP
+about-webrtc-sdp-parsing-errors-heading = Gwallau Didoli SDP
+
+##
+
+# "RTP" is an abbreviation for the Real-time Transport Protocol, an IETF
+# specification, and should not normally be translated. "Stats" is an
+# abbreviation for Statistics.
+about-webrtc-rtp-stats-heading = Ystadegau RTP
+
+## "ICE" is an abbreviation for Interactive Connectivity Establishment, which
+## is an IETF protocol, and should not normally be translated.
+
+about-webrtc-ice-state = Cyflwr ICE
+# "Stats" is an abbreviation for Statistics.
+about-webrtc-ice-stats-heading = Ystadegau ICE
+about-webrtc-ice-restart-count-label = Ailgychwyn ICE:
+about-webrtc-ice-rollback-count-label = Hen fersiynau ICE:
+about-webrtc-ice-pair-bytes-sent = Didau wedi'u hanfon:
+about-webrtc-ice-pair-bytes-received = Didau wedi'u derbyn:
+about-webrtc-ice-component-id = Enw'r Cydran
+
+##
+
+
+## "Avg." is an abbreviation for Average. These are used as data labels.
+
+about-webrtc-avg-bitrate-label = Di-radd cyfartalog:
+about-webrtc-avg-framerate-label = Ffrâm-radd cyfartalog:
+
+##
+
+
+## These adjectives are used to label a line of statistics collected for a peer
+## connection. The data represents either the local or remote end of the
+## connection.
+
+about-webrtc-type-local = Lleol
+about-webrtc-type-remote = Pell
+
+##
+
+# This adjective is used to label a table column. Cells in this column contain
+# the localized javascript string representation of "true" or are left blank.
+about-webrtc-nominated = Enwebwyd
+# This adjective is used to label a table column. Cells in this column contain
+# the localized javascript string representation of "true" or are left blank.
+# This represents an attribute of an ICE candidate.
+about-webrtc-selected = Dewiswyd
+about-webrtc-save-page-label = Cadw Tudalen
+about-webrtc-debug-mode-msg-label = Modd Dadfygio
+about-webrtc-debug-mode-off-state-label = Cychwyn y Modd Dadfygio
+about-webrtc-debug-mode-on-state-label = Atal y Modd Dadfygio
+about-webrtc-stats-heading = Ystadegau'r Sesiwn
+about-webrtc-stats-clear = Clirio Hanes
+about-webrtc-log-heading = Cofnod Cysylltu
+about-webrtc-log-clear = Clirio'r Cofnod
+about-webrtc-log-show-msg = dangos cofnod
+    .title = cliciwch i ehangu'r adran
+about-webrtc-log-hide-msg = cuddio cofnod
+    .title = cliciwch i gau'r adran
+
+## These are used to display a header for a PeerConnection.
+## Variables:
+##  $browser-id (Number) - A numeric id identifying the browser tab for the PeerConnection.
+##  $id (String) - A globally unique identifier for the PeerConnection.
+##  $url (String) - The url of the site which opened the PeerConnection.
+##  $now (Date) - The JavaScript timestamp at the time the report was generated.
+
+about-webrtc-connection-open = [ { $browser-id } | { $id } ] { $url } { $now }
+about-webrtc-connection-closed = [ { $browser-id } | { $id } ] { $url } (cau) { $now }
+
+##
+
+about-webrtc-local-candidate = Ymgeisydd Lleol
+about-webrtc-remote-candidate = Ymgeisydd Pell
+about-webrtc-raw-candidates-heading = Pob Ymgeisydd Bras
+about-webrtc-raw-local-candidate = Ymgeisydd Lleol Bras
+about-webrtc-raw-remote-candidate = Ymgeisydd Pell Bras
+about-webrtc-raw-cand-show-msg = dangos ymgeiswyr bras
+    .title = cliciwch i ehangu'r adran
+about-webrtc-raw-cand-hide-msg = cuddio ymgeiswyr bras
+    .title = cliciwch i gau'r adran
+about-webrtc-priority = Blaenoriaeth
+about-webrtc-fold-show-msg = dangos manylion
+    .title = cliciwch i ehangu'r adran
+about-webrtc-fold-hide-msg = cuddio manylion
+    .title = cliciwch i gau'r adran
+about-webrtc-dropped-frames-label = Fframiau wedi'u gollwng:
+about-webrtc-discarded-packets-label = Pecynnau wedi'u hepgor:
+about-webrtc-decoder-label = Datgodwyr
+about-webrtc-encoder-label = Amgodiwr
+about-webrtc-show-tab-label = Dangos tab
+about-webrtc-width-px = Lled (px)
+about-webrtc-height-px = Uchder (px)
+about-webrtc-consecutive-frames = Fframiau Olynol
+about-webrtc-time-elapsed = Amser wedi Pasio
+about-webrtc-estimated-framerate = Amcan o Raddfa Ffrâm
+about-webrtc-rotation-degrees = Cylchdroi (graddau)
+about-webrtc-first-frame-timestamp = Stamp Amser Derbyn y  Ffrâm Gyntaf
+about-webrtc-last-frame-timestamp = Stamp Amser Derbyn y  Ffrâm Olaf
+
+## SSRCs are identifiers that represent endpoints in an RTP stream
+
+# This is an SSRC on the local side of the connection that is receiving RTP
+about-webrtc-local-receive-ssrc = Derbyn SSRC  Lleol
+# This is an SSRC on the remote side of the connection that is sending RTP
+about-webrtc-remote-send-ssrc = Anfon SSRC o Bell
+
+##
+
+# An option whose value will not be displayed but instead noted as having been
+# provided
+about-webrtc-configuration-element-provided = Wedi'i Ddarparu
+# An option whose value will not be displayed but instead noted as having not
+# been provided
+about-webrtc-configuration-element-not-provided = Heb ei Ddarparu
+# The options set by the user in about:config that could impact a WebRTC call
+about-webrtc-custom-webrtc-configuration-heading = Dewisiadau WebRTC Gosodedig y Defnyddiwr
+# Section header for estimated bandwidths of WebRTC media flows
+about-webrtc-bandwidth-stats-heading = Amcangyfrif Lled Band
+# The ID of the MediaStreamTrack
+about-webrtc-track-identifier = Dynodwr tracio
+# The estimated bandwidth available for sending WebRTC media in bytes per second
+about-webrtc-send-bandwidth-bytes-sec = Lled Band Anfon (beit/eiliad)
+# The estimated bandwidth available for receiving WebRTC media in bytes per second
+about-webrtc-receive-bandwidth-bytes-sec = Lled Band Derbyn (beit/eiliad)
+# Maximum number of bytes per second that will be padding zeros at the ends of packets
+about-webrtc-max-padding-bytes-sec = Uchafswm Padio (beit/eiliad)
+# The amount of time inserted between packets to keep them spaced out
+about-webrtc-pacer-delay-ms = Oedi Pacer ms
+# The amount of time it takes for a packet to travel from the local machine to the remote machine,
+# and then have a packet return
+about-webrtc-round-trip-time-ms = RTT ms
+# This is a section heading for video frame statistics for a MediaStreamTrack.
+# see https://developer.mozilla.org/en-US/docs/Web/API/MediaStreamTrack.
+# Variables:
+#   $track-identifier (String) - The unique identifier for the MediaStreamTrack.
+about-webrtc-frame-stats-heading = Ystadegau Ffrâm Fideo - MediaStreamTrack ID: { $track-identifier }
+
+## These are paths used for saving the about:webrtc page or log files so
+## they can be attached to bug reports.
+## Variables:
+##  $path (String) - The path to which the file is saved.
+
+about-webrtc-save-page-msg = cadwyd y dudalen i: { $path }
+about-webrtc-debug-mode-off-state-msg = mae modd canfod y cofnod olrhain yn: { $path }
+about-webrtc-debug-mode-on-state-msg = modd dadfygio'n weithredol, cofnod olrhain yn { $path }
+about-webrtc-aec-logging-off-state-msg = mae'r ffeiliau cofnod y cipio yn: { $path }
+
+##
+
+# This is the total number of packets received on the PeerConnection.
+# Variables:
+#  $packets (Number) - The number of packets received.
+about-webrtc-received-label =
+    { $packets ->
+        [zero] Heb dderbyn unrhyw becyn
+        [one] Wedi derbyn { $packets } pecyn
+        [two] Wedi derbyn { $packets } pecyn
+        [few] Wedi derbyn { $packets } pecyn
+        [many] Wedi derbyn { $packets } pecyn
+       *[other] Wedi derbyn { $packets } pecyn
+    }
+# This is the total number of packets lost by the PeerConnection.
+# Variables:
+#  $packets (Number) - The number of packets lost.
+about-webrtc-lost-label =
+    { $packets ->
+        [zero] Heb golli unrhyw becyn
+        [one] Wedi derbyn { $packets } pecyn
+        [two] Wedi derbyn { $packets } pecyn
+        [few] Wedi derbyn { $packets } pecyn
+        [many] Wedi derbyn { $packets } pecyn
+       *[other] Wedi derbyn { $packets } pecyn
+    }
+# This is the total number of packets sent by the PeerConnection.
+# Variables:
+#  $packets (Number) - The number of packets sent.
+about-webrtc-sent-label =
+    { $packets ->
+        [zero] Heb anfon unrhyw becyn
+        [one] Wedi anfon { $packets } pecyn
+        [two] Wedi anfon { $packets } pecyn
+        [few] Wedi anfon { $packets } pecyn
+        [many] Wedi anfon { $packets } pecyn
+       *[other] Wedi anfon { $packets } pecyn
+    }
+# Jitter is the variance in the arrival time of packets.
+# See: https://w3c.github.io/webrtc-stats/#dom-rtcreceivedrtpstreamstats-jitter
+# Variables:
+#   $jitter (Number) - The jitter.
+about-webrtc-jitter-label = Jitter { $jitter }
+# ICE candidates arriving after the remote answer arrives are considered trickled
+# (an attribute of an ICE candidate). These are highlighted in the ICE stats
+# table with light blue background.
+about-webrtc-trickle-caption-msg = Mae ymgeisydd diferu (yn cyrraedd ar ôl yr ateb) yn cael eu hamlygu mewn glas
+
+## "SDP" is an abbreviation for Session Description Protocol, an IETF standard.
+## See http://wikipedia.org/wiki/Session_Description_Protocol
+
+# This is used as a header for local SDP.
+# Variables:
+#  $timestamp (Number) - The Unix Epoch time at which the SDP was set.
+about-webrtc-sdp-set-at-timestamp-local = Gosod SDP lleol ar y stamp amser { NUMBER($timestamp, useGrouping: "false") }.
+# This is used as a header for remote SDP.
+# Variables:
+#  $timestamp (Number) - The Unix Epoch time at which the SDP was set.
+about-webrtc-sdp-set-at-timestamp-remote = Gosod SDP pell ar y stamp amser { NUMBER($timestamp, useGrouping: "false") }.
+# This is used as a header for an SDP section contained in two columns allowing for side-by-side comparisons.
+# Variables:
+#  $timestamp (Number) - The Unix Epoch time at which the SDP was set.
+#  $relative-timestamp (Number) - The timestamp relative to the timestamp of the earliest received SDP.
+about-webrtc-sdp-set-timestamp = Stamp amser { NUMBER($timestamp, useGrouping: "false") } (+ { $relative-timestamp } ms)
+
+##
+
diff --git a/l10n-cy/toolkit/toolkit/about/abuseReports.ftl b/l10n-cy/toolkit/toolkit/about/abuseReports.ftl
new file mode 100644
index 0000000000..c05339c2a8
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/about/abuseReports.ftl
@@ -0,0 +1,101 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# Localized string used as the dialog window title (a new behavior locked
+# behind the "extensions.abuseReport.openDialog" preference).
+# "Report" is a noun in this case, "Report for AddonName".
+#
+# Variables:
+#   $addon-name (string) - Name of the add-on being reported
+abuse-report-dialog-title = Adrodd am { $addon-name }
+
+abuse-report-title-extension = Adroddwch yr Estyniad hwn i { -vendor-short-name }
+abuse-report-title-theme = Adroddwch y Thema hon i { -vendor-short-name }
+abuse-report-subtitle = Beth yw'r broblem?
+
+# Variables:
+#   $author-name (string) - Name of the add-on author
+abuse-report-addon-authored-by = gan <a data-l10n-name="author-name">{ $author-name }</a>
+
+abuse-report-learnmore =
+    Ddim yn siŵr pa fater i'w ddewis?
+    <a data-l10n-name="learnmore-link">Dysgwch fwy am adrodd ar estyniadau a themâu</a>
+
+abuse-report-submit-description = Disgrifiwch y broblem (dewisol)
+abuse-report-textarea =
+    .placeholder = Mae'n haws i ni fynd i'r afael â phroblem os oes gennym fanylion penodol. Disgrifiwch yr hyn rydych chi'n ei brofi. Diolch i chi am ein helpu i gadw'r we'n iach.
+abuse-report-submit-note =
+    Sylwer: Peidiwch â chynnwys gwybodaeth bersonol (fel enw, cyfeiriad e-bost, rhif ffôn, cyfeiriad corfforol).
+    Mae { -vendor-short-name } yn cadw cofnod parhaol o'r adroddiadau hyn.
+
+## Panel buttons.
+
+abuse-report-cancel-button = Diddymu
+abuse-report-next-button = Nesaf
+abuse-report-goback-button = Mynd nôl
+abuse-report-submit-button = Cyflwyno
+
+## Message bars descriptions.
+
+
+## Variables:
+##   $addon-name (string) - Name of the add-on
+
+abuse-report-messagebar-aborted = Diddymwyd yr adroddiad ar gyfer <span data-l10n-name="addon-name">{ $addon-name }</span>>.
+abuse-report-messagebar-submitting = Anfon adroddiad ar gyfer <span data-l10n-name="addon-name">{ $addon-name }</span>.
+abuse-report-messagebar-submitted = Diolch i chi am gyflwyno adroddiad. Ydych chi am gael gwared ar <span data-l10n-name="addon-name">{ $addon-name }</span>?
+abuse-report-messagebar-submitted-noremove = Diolch am gyflwyno adroddiad.
+abuse-report-messagebar-removed-extension = Diolch i chi am gyflwyno adroddiad. Rydych wedi tynnu'r estyniad <span data-l10n-name="addon-name">{ $addon-name }</span>.
+abuse-report-messagebar-removed-theme = Diolch i chi am gyflwyno adroddiad. Rydych chi wedi tynnu'r thema <span data-l10n-name="addon-name">{ $addon-name }</span>
+abuse-report-messagebar-error = Roedd gwall wrth anfon yr adroddiad ar gyfer <span data-l10n-name="addon-name">{ $addon-name }</span>.
+abuse-report-messagebar-error-recent-submit = Nid yw'r adroddiad ar gyfer <span data-l10n-name="addon-name">{ $addon-name }</span> wedi ei anfon oherwydd bod adroddiad arall wedi'i gyflwyno'n ddiweddar.
+
+## Message bars actions.
+
+abuse-report-messagebar-action-remove-extension = Iawn, Dileu
+abuse-report-messagebar-action-keep-extension = Na, rwyf am ei gadw
+abuse-report-messagebar-action-remove-theme = Iawn, Dileu
+abuse-report-messagebar-action-keep-theme = Na, rwyf am ei gadw
+abuse-report-messagebar-action-retry = Ceisio eto
+abuse-report-messagebar-action-cancel = Diddymu
+
+## Abuse report reasons (optionally paired with related examples and/or suggestions)
+
+abuse-report-damage-reason-v2 = Fe wnaeth niweidio fy nghyfrifiadur neu gyfaddawdu ar fy nata
+abuse-report-damage-example = Enghraifft: Chwistrellu data maleisus neu ddata wedi'i ddwyn
+
+abuse-report-spam-reason-v2 = Mae'n cynnwys sbam neu'n mewnosod hysbysebu dieisiau
+abuse-report-spam-example = Enghraifft: Mewnosod hysbysebion ar dudalennau gwe
+
+abuse-report-settings-reason-v2 = Newidiodd fy mheiriant chwilio, hafan, neu dab newydd heb roi gwybod na gofyn imi
+abuse-report-settings-suggestions = Cyn adrodd ar yr estyniad, gallwch roi cynnig ar newid eich gosodiadau:
+abuse-report-settings-suggestions-search = Newid eich gosodiadau chwilio rhagosodedig
+abuse-report-settings-suggestions-homepage = Newidiwch eich tudalen gartref a'ch tab newydd
+
+abuse-report-deceptive-reason-v2 = Mae'n honni ei fod yn rhywbeth nad ydyw
+abuse-report-deceptive-example = Enghraifft: Disgrifiad neu ddelweddau camarweiniol
+
+abuse-report-broken-reason-extension-v2 = Nid yw'n gweithio, mae'n torri gwefannau, neu'n arafu { -brand-product-name }
+abuse-report-broken-reason-theme-v2 = Nid yw'n gweithio nac yn torri dangosydd y porwr
+abuse-report-broken-example = Enghraifft: Mae nodwedd yn araf, yn anodd ei defnyddio, neu ddim yn gweithio; ni fydd rhannau o wefannau yn llwytho neu'n edrych yn rhyfedd
+abuse-report-broken-suggestions-extension =
+    Mae'n edrych fel eich bod wedi adnabod gwall. Yn ogystal â chyflwyno adroddiad yma, y ffordd orau
+    orau i ddatrys mater ymarferoldeb wedi'i ddatrys yw cysylltu â datblygwr yr estyniad.
+    <a data-l10n-name="support-link">Ewch i wefan yr estyniad</a> i gael gwybodaeth gan y datblygwr.
+abuse-report-broken-suggestions-theme =
+    Mae'n edrych fel eich bod wedi adnabod gwall. Yn ogystal â chyflwyno adroddiad yma, y ffordd orau
+    orau i ddatrys mater ymarferoldeb wedi'i ddatrys yw cysylltu â datblygwr y thema.
+    <a data-l10n-name="support-link"> Ewch i wefan y thema </a> i gael gwybodaeth y datblygwr.
+
+abuse-report-policy-reason-v2 = Mae'n cynnwys cynnwys atgas, treisgar neu anghyfreithlon
+abuse-report-policy-suggestions =
+    Sylw: Rhaid rhoi gwybod am faterion hawlfraint a nod masnach mewn proses ar wahân.
+    <a data-l10n-name="report-infringement-link"> Defnyddiwch y cyfarwyddiadau hyn</a> i
+    adrodd am y broblem.
+
+abuse-report-unwanted-reason-v2 = Doeddwn i erioed ei eisiau ac nid wyf yn gwybod sut i gael gwared arno
+abuse-report-unwanted-example = Enghraifft: Gosodwyd y rhaglen heb fy nghaniatâd
+
+abuse-report-other-reason = Rhywbeth arall
+
diff --git a/l10n-cy/toolkit/toolkit/about/certviewer.ftl b/l10n-cy/toolkit/toolkit/about/certviewer.ftl
new file mode 100644
index 0000000000..7ddb427143
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/about/certviewer.ftl
@@ -0,0 +1,120 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+certificate-viewer-certificate-section-title = Tystysgrif
+
+## Error messages
+
+certificate-viewer-error-message = Nid oeddem yn gallu dod o hyd i fanylion y dystysgrif, neu mae'r dystysgrif yn llygredig. Ceisiwch eto.
+certificate-viewer-error-title = Aeth rhywbeth o'i le.
+
+## Certificate information labels
+
+certificate-viewer-algorithm = Algorithm
+certificate-viewer-certificate-authority = Awdurdod Tystysgrif
+certificate-viewer-cipher-suite = Casgliad Seiffr
+certificate-viewer-common-name = Enw Cyffredin
+certificate-viewer-email-address = Cyfeiriad E-bost
+# Variables:
+#   $firstCertName (String) - Common Name for the displayed certificate
+certificate-viewer-tab-title = Tystysgrif ar gyfer { $firstCertName }
+# Inc. means Incorporated, e.g GitHub is incorporated in Delaware
+certificate-viewer-inc-country = Gwlad Corfforedig
+certificate-viewer-country = Gwlad
+certificate-viewer-curve = Cromlin
+certificate-viewer-distribution-point = Pwynt Dosbarthu
+certificate-viewer-dns-name = Enw DNS
+certificate-viewer-ip-address = Cyfeiriad IP
+certificate-viewer-other-name = Enw Arall
+certificate-viewer-exponent = Esbonydd
+certificate-viewer-id = ID
+certificate-viewer-key-exchange-group = Grŵp Cyfnewid Allwedd
+certificate-viewer-key-id = ID Allwedd
+certificate-viewer-key-size = Maint Allwedd
+# Inc. means Incorporated, e.g GitHub is incorporated in Delaware
+certificate-viewer-inc-locality = Ardal Corffori
+certificate-viewer-locality = Lleoliad
+certificate-viewer-location = Lleoliad
+certificate-viewer-logid = ID Cofnod
+certificate-viewer-method = Dull
+certificate-viewer-modulus = Modwlws
+certificate-viewer-name = Enw
+certificate-viewer-not-after = Nid ar Ôl
+certificate-viewer-not-before = Nid Cyn
+certificate-viewer-organization = Corff
+certificate-viewer-organizational-unit = Uned Corff
+certificate-viewer-policy = Polisi
+certificate-viewer-protocol = Protocol
+certificate-viewer-public-value = Gwerth Cyhoeddus
+certificate-viewer-purposes = Pwrpasau
+certificate-viewer-qualifier = Cymhwyster
+certificate-viewer-qualifiers = Cymhwysterau
+certificate-viewer-required = Gofynnol
+certificate-viewer-unsupported = &lt;heb ei gynnal&gt;
+# Inc. means Incorporated, e.g GitHub is incorporated in Delaware
+certificate-viewer-inc-state-province = Corfforedig Talaith/Ardal
+certificate-viewer-state-province = Talaith/Ardal
+certificate-viewer-sha-1 = SHA-1
+certificate-viewer-sha-256 = SHA-256
+certificate-viewer-serial-number = Rhif Cyfresol
+certificate-viewer-signature-algorithm = Algorithm Llofnod
+certificate-viewer-signature-scheme = Cynllun Llofnod
+certificate-viewer-timestamp = Stamp Amser
+certificate-viewer-value = Gwerth
+certificate-viewer-version = Fersiwn
+certificate-viewer-business-category = Categori Busnes
+certificate-viewer-subject-name = Enw'r Pwnc
+certificate-viewer-issuer-name = Enw Cyhoeddwr
+certificate-viewer-validity = Dilysrwydd
+certificate-viewer-subject-alt-names = Enwau Alt Pwnc
+certificate-viewer-public-key-info = Manylion Allweddol Cyhoeddus
+certificate-viewer-miscellaneous = Amrywiol
+certificate-viewer-fingerprints = Bysbrint
+certificate-viewer-basic-constraints = Cyfyngiadau Sylfaenol
+certificate-viewer-key-usages = Defnyddiau Allweddol
+certificate-viewer-extended-key-usages = Defnydd Allwedd Estynedig
+certificate-viewer-ocsp-stapling = Strapio OCSP
+certificate-viewer-subject-key-id = ID Allwedd Pwnc
+certificate-viewer-authority-key-id = ID Allwedd yr Awdurdod
+certificate-viewer-authority-info-aia = Manylion yr Awdurdod (AIA)
+certificate-viewer-certificate-policies = Polisïau Tystysgrif
+certificate-viewer-embedded-scts = SCTs mewnblanedig
+certificate-viewer-crl-endpoints = Diweddbwynt CRL
+# This message is used as a row header in the Miscellaneous section.
+# The associated data cell contains links to download the certificate.
+certificate-viewer-download = Llwytho i Lawr
+# This message is used to replace boolean values (true/false) in several certificate fields, e.g. Certificate Authority
+# Variables:
+#   $boolean (String) - true/false value for the specific field
+certificate-viewer-boolean =
+    { $boolean ->
+        [true] Iawn
+       *[false] na
+    }
+
+## Variables:
+##   $fileName (String) - The file name to save the PEM data in, derived from the common name from the certificate being displayed.
+
+certificate-viewer-download-pem = PEM (tystysgrif)
+    .download = { $fileName }.pem
+certificate-viewer-download-pem-chain = PEM (cadwyn)
+    .download = { $fileName }-chain.pem
+# The title attribute for Critical Extension icon
+certificate-viewer-critical-extension =
+    .title = Mae'r estyniad hwn wedi'i nodi fel un hanfodol, sy'n golygu bod yn rhaid i gleientiaid wrthod y dystysgrif os nad ydyn nhw'n ei deall.
+certificate-viewer-export = Allforio
+    .download = { $fileName }.pem
+
+##
+
+# Label for a tab where we haven't found a better label:
+certificate-viewer-unknown-group-label = (anhysbys)
+
+## Labels for tabs displayed in stand-alone about:certificate page
+
+certificate-viewer-tab-mine = Eich Tystysgrifau
+certificate-viewer-tab-people = Pobl
+certificate-viewer-tab-servers = Gweinyddion
+certificate-viewer-tab-ca = Awdurdodau
+certificate-viewer-tab-unkonwn = Anhysbys
diff --git a/l10n-cy/toolkit/toolkit/about/config.ftl b/l10n-cy/toolkit/toolkit/about/config.ftl
new file mode 100644
index 0000000000..d9621d4a2c
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/about/config.ftl
@@ -0,0 +1,51 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+## These strings appear on the warning you see when first visiting about:config.
+
+about-config-intro-warning-title = Byddwch Ofalus
+about-config-intro-warning-text = Gall newid dewisiadau ffurfweddiad uwch effeithio ar berfformiad neu ddiogelwch { -brand-short-name }.
+about-config-intro-warning-checkbox = Rhybuddiwch fi pan fyddaf yn ceisio mynd at y dewisiadau hyn
+about-config-intro-warning-button = Derbyn y Perygl a Pharhau
+
+##
+
+# This is shown on the page before searching but after the warning is accepted.
+about-config-caution-text = Gall newid dewisiadau ffurfweddiad uwch effeithio ar berfformiad neu ddiogelwch { -brand-short-name }.
+about-config-page-title = Dewisiadau Uwch
+about-config-search-input1 =
+    .placeholder = Enw dewis chwilio
+about-config-show-all = Dangos Popeth
+about-config-show-only-modified = Dangos dewisiadau wedi'u haddasu yn unig
+about-config-pref-add-button =
+    .title = Ychwanegu
+about-config-pref-toggle-button =
+    .title = Toglo
+about-config-pref-edit-button =
+    .title = Golygu
+about-config-pref-save-button =
+    .title = Cadw
+about-config-pref-reset-button =
+    .title = Ailosod
+about-config-pref-delete-button =
+    .title = Dileu
+
+## Labels for the type selection radio buttons shown when adding preferences.
+
+about-config-pref-add-type-boolean = Boole
+about-config-pref-add-type-number = Rhif
+about-config-pref-add-type-string = Llinyn
+
+## Preferences with a non-default value are differentiated visually, and at the
+## same time the state is made accessible to screen readers using an aria-label
+## that won't be visible or copied to the clipboard.
+##
+## Variables:
+##   $value (String): The full value of the preference.
+
+about-config-pref-accessible-value-default =
+    .aria-label = { $value } (default)
+about-config-pref-accessible-value-custom =
+    .aria-label = { $value } (custom)
diff --git a/l10n-cy/toolkit/toolkit/about/url-classifier.ftl b/l10n-cy/toolkit/toolkit/about/url-classifier.ftl
new file mode 100644
index 0000000000..0c91ecb91e
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/about/url-classifier.ftl
@@ -0,0 +1,54 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+url-classifier-title = Manylion Dosbarthu URL
+url-classifier-search-title = Chwilio
+url-classifier-search-result-title = Canlyniadau
+url-classifier-search-result-uri = URI: { $uri }
+url-classifier-search-result-list = Rhestr tablau: { $list }
+url-classifier-search-input = URL
+url-classifier-search-error-invalid-url = URL annilys
+url-classifier-search-error-no-features = Heb ddewis nodwedd
+url-classifier-search-btn = Cychwyn chwilio
+url-classifier-search-features = Nodweddion
+url-classifier-search-listType = Math o restr
+url-classifier-provider-title = Darparwr
+url-classifier-provider = Darparwr
+url-classifier-provider-last-update-time = Amser y diweddariad diwethaf
+url-classifier-provider-next-update-time = Amser y diweddariad nesaf
+url-classifier-provider-back-off-time = Amser atal
+url-classifier-provider-last-update-status = Statws y diweddariad diwethaf
+url-classifier-provider-update-btn = Diweddaru
+url-classifier-cache-title = Storfa Dros Dro
+url-classifier-cache-refresh-btn = Adnewyddu
+url-classifier-cache-clear-btn = Clirio
+url-classifier-cache-table-name = Enw tabl
+url-classifier-cache-ncache-entries = Nifer o gofnodion storfa dros dro negyddol
+url-classifier-cache-pcache-entries = Nifer o gofnodion storfa dros dro negyddol
+url-classifier-cache-show-entries = Dangos y cofnodion
+url-classifier-cache-entries = Cofnodion Storfa Dros Dro
+url-classifier-cache-prefix = Rhagddodiad
+url-classifier-cache-ncache-expiry = Storfa dros dro negyddol yn dod i ben
+url-classifier-cache-fullhash = Hash llawn
+url-classifier-cache-pcache-expiry = Storfa dros dro positif yn dod i ben
+url-classifier-debug-title = Dadfygio
+url-classifier-debug-module-btn = Gosod Modiwlau Cofnodi
+url-classifier-debug-file-btn = Gosod Ffeil Cofnodi
+url-classifier-debug-js-log-chk = Gosod Cofnod JS
+url-classifier-debug-sb-modules = Modiwlau cofnodi Pori Diogel
+url-classifier-debug-modules = Y modiwlau cofnodi cyfredol
+url-classifier-debug-sbjs-modules = Cofnod Pori Diogel JS
+url-classifier-debug-file = Ffeil cofnod cyfredol
+
+url-classifier-trigger-update = Diweddariad Triger
+url-classifier-not-available = Dim Ar Gael
+url-classifier-disable-sbjs-log = Analluogi Cofnod JS Pori Diogel
+url-classifier-enable-sbjs-log = Galluogi Cofnod JS Pori Diogel
+url-classifier-enabled = Galluogwyd
+url-classifier-disabled = Analluogwyd
+url-classifier-updating = diweddaru
+url-classifier-cannot-update = methu diweddaru
+url-classifier-success = llwyddiant
+url-classifier-update-error = gwall diweddaru ({ $error })
+url-classifier-download-error = gwall llwytho i lawr ({ $error })
diff --git a/l10n-cy/toolkit/toolkit/extensions/blocklist.ftl b/l10n-cy/toolkit/toolkit/extensions/blocklist.ftl
new file mode 100644
index 0000000000..efec01a975
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/extensions/blocklist.ftl
@@ -0,0 +1,22 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0
+
+blocklist-window =
+    .title = Mae Ychwanegion yn gallu achosi problemau
+    .style = width: 45em; height: 30em
+blocklist-accept =
+    .label = Ailgychwyn { -brand-short-name }
+    .accesskey = A
+
+blocklist-label-summary = Mae { -brand-short-name } wedi canfod fod yr ychwanegion canlynol yn gallu creu ansefydlogrwydd neu broblemau diogelwch:
+blocklist-soft-and-hard = Mae'r ychwanegion sydd â risg uchel o achosi problemau wedi eu rhwystro. Mae'r lleill o risg is, ond argymhellir yn gryf eich bod yn ailgychwyn gyda nhw wedi eu hanalluogi.
+blocklist-hard-blocked = Mae'r ychwanegion hyn a thebygrwydd uchel o achosi problemau ac maent wedi eu rhwystro, ond bydd angen ailgychwyn i'w hanalluogi yn llwyr.
+blocklist-soft-blocked = Er eich diogelwch, argymhellir eich bod yn ailgychwyn gyda'r ychwanegion hyn wedi eu hanalluogi.
+blocklist-more-information =
+    .value = Rhagor o wybodaeth
+
+blocklist-blocked =
+    .label = Rhwystrwyd
+blocklist-checkbox =
+    .label = Anablu
diff --git a/l10n-cy/toolkit/toolkit/featuregates/features.ftl b/l10n-cy/toolkit/toolkit/featuregates/features.ftl
new file mode 100644
index 0000000000..3e0b56c79a
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/featuregates/features.ftl
@@ -0,0 +1,107 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# The title of the experiment should be kept in English as it may be referenced
+# by various online articles and is technical in nature.
+experimental-features-css-masonry2 =
+    .label = CSS: Masonry Layout
+experimental-features-css-masonry-description = Yn galluogi cefnogaeth i nodwedd arbrofol Cynllun Masonry CSS. Gw. yr <a data-l10n-name="explainer">esboniwr</a> i gael disgrifiad lefel uchel o'r nodwedd. I ddarparu adborth, rhowch sylwadau yn <a data-l10n-name="w3c-issue">y mater GitHub hwn</a> neu <a data-l10n-name="bug">y byg hwn</a>.
+# The title of the experiment should be kept in English as it may be referenced
+# by various online articles and is technical in nature.
+experimental-features-web-gpu2 =
+    .label = Web API: WebGPU
+experimental-features-web-gpu-description2 = Mae'r API newydd hwn yn darparu cefnogaeth lefel isel ar gyfer perfformio cyfrifiant a rendro graffeg gan ddefnyddio <a data-l10n-name="wikipedia">Uned Prosesu Graffeg (GPU)</a> dyfais neu gyfrifiadur y defnyddiwr. Mae'r <a data-l10n-name="spec">fanyleb </a> yn dal i fod yn waith ar y gweill. Gweler <a data-l10n-name="bugzilla">bug 1602129</a> am fwy o fanylion.
+# The title of the experiment should be kept in English as it may be referenced
+# by various online articles and is technical in nature.
+experimental-features-media-avif =
+    .label = Media: AVIF
+experimental-features-media-avif-description = Gyda'r nodwedd hon wedi'i galluogi, mae { -brand-short-name } yn cefnogi fformat Ffeil Delwedd AV1 (AVIF). Mae hwn yn fformat ffeil delwedd llonydd sy'n trosoli galluoedd yr algorithmau cywasgu fideo AV1 i leihau maint delwedd. Gweler <a data-l10n-name="bugzilla">bug 1443863</a> am fwy o fanylion.
+# The title of the experiment should be kept in English as it may be referenced
+# by various online articles and is technical in nature.
+experimental-features-web-api-inputmode =
+    .label = Web API: inputmode
+# "inputmode" and "contenteditable" are technical terms and shouldn't be translated.
+experimental-features-web-api-inputmode-description = Mae ein gweithrediad o'r priodoledd byd-eang <a data-l10n-name="mdn-inputmode">inputmode</a> wedi'i ddiweddaru yn unol â <a data-l10n-name="whatwg">manyleb WHATWG</a>, ond mae angen i ni wneud newidiadau eraill o hyd hefyd, fel sicrhau ei fod ar gael ar gynnwys adolygadwy. Gweler <a data-l10n-name="bugzilla">bug 1205133</a> am fwy o fanylion.
+# The title of the experiment should be kept in English as it may be referenced
+# by various online articles and is technical in nature.
+experimental-features-web-api-link-preload =
+    .label = Web API: <link rel="preload">
+# Do not translate "rel", "preload" or "link" here, as they are all HTML spec
+# values that do not get translated.
+experimental-features-web-api-link-preload-description = Bwriad y briodoledd <a data-l10n-name="rel">rel</a> gyda gwerth <code>"preload"</code> ar <a data-l10n-name="link">&lt;dolen&gt;</a> yw helpu i ddarparu enillion perfformiad trwy adael i chi lwytho adnoddau i lawr yn gynharach yng nghylch bywyd y dudalen, gan sicrhau eu bod ar gael yn gynharach a'u bod yn llai tebygol o rwystro rendro tudalennau. Darllenwch <a data-l10n-name="readmore">“Rhag-lwytho cynnwys gyda<code> rel =" preload "</code>”</a> neu gweler <a data-l10n-name="bugzilla">bug 1583604</a> am fwy o fanylion.
+# The title of the experiment should be kept in English as it may be referenced
+# by various online articles and is technical in nature.
+experimental-features-css-focus-visible =
+    .label = CSS: Pseudo-class: :focus-visible
+experimental-features-css-focus-visible-description = Yn caniatáu i arddulliau ffocws gael eu cymhwyso i elfennau fel botymau a rheolyddion ffurf, dim ond pan fyddan nhw'n canolbwyntio gan ddefnyddio'r bysellfwrdd (e.e. wrth dabio rhwng elfennau), ac nid pan fyddan nhw'n canolbwyntio gan ddefnyddio llygoden neu ddyfais bwyntio arall. Gweler <a data-l10n-name="bugzilla">bug 1617600</a> am fwy o fanylion.
+# The title of the experiment should be kept in English as it may be referenced
+# by various online articles and is technical in nature.
+experimental-features-web-api-beforeinput =
+    .label = Web API: beforeinput Event
+# The terms "beforeinput", "input", "textarea", and "contenteditable" are technical terms
+# and shouldn't be translated.
+experimental-features-web-api-beforeinput-description = Mae'r digwyddiad cyffredinol <a data-l10n-name="mdn-beforeinput">beforeinput</a> yn cael ei danio ar ddigwyddiad <a data-l10n-name="mdn-input">&lt;input&gt;</a> a < a data-l10n-name = "mdn-textarea">&lt;textarea&gt;</a> elfennau, neu unrhyw elfen y mae ei briodoledd <a data-l10n-name="mdn-contenteditable">cynnwys adolygadwy</a> wedi'i alluogi, yn union cyn i werth yr elfen newid. Mae'r digwyddiad yn caniatáu i apiau gwe ddiystyru ymddygiad rhagosodedig y porwr ar gyfer rhyngweithio â defnyddwyr, e.e., gall apiau gwe ddiddymu mewnbwn defnyddiwr yn unig ar gyfer nodau penodol neu gallan nhw addasu gludo testun â steil yn unig gydag arddulliau cymeradwy.
+# The title of the experiment should be kept in English as it may be referenced
+# by various online articles and is technical in nature.
+experimental-features-css-constructable-stylesheets =
+    .label = CSS: Constructable Stylesheets
+experimental-features-css-constructable-stylesheets-description = Mae ychwanegu adeiladwr at y rhyngwyneb <a data-l10n-name="mdn-cssstylesheet">CSSStyleSheet</a> yn ogystal ag amrywiaeth o newidiadau cysylltiedig yn ei gwneud hi'n bosibl creu taflenni arddull newydd yn uniongyrchol heb orfod ychwanegu'r ddalen at yr HTML. Mae hyn yn ei gwneud hi'n llawer haws creu taflenni arddull y mae modd eu hailddefnyddio i'w defnyddio gyda <a data-l10n-name="mdn-shadowdom">Shadow DOM</a>. Gweler <a data-l10n-name="bugzilla">bug 1520690</a> am fwy o fanylion.
+experimental-features-devtools-color-scheme-simulation =
+    .label = Developer Tools: Color Scheme Simulation
+experimental-features-devtools-color-scheme-simulation-description = Yn ychwanegu opsiwn i efelychu gwahanol gynlluniau lliw sy'n eich galluogi i brofi <a data-l10n-name="mdn-preferscolorscheme">@prefers-color-scheme</a> ymholiadau cyfryngau. Mae defnyddio'r ymholiad cyfryngau hwn yn caniatáu i'ch taflen arddull ymateb i p'un a yw'n well gan y defnyddiwr ryngwyneb defnyddiwr ysgafn neu dywyll. Mae'r nodwedd hon yn caniatáu ichi brofi'ch cod heb orfod newid gosodiadau yn eich porwr (neu system weithredu, os yw'r porwr yn dilyn gosodiad cynllun lliw ar draws y system). Gweler <a data-l10n-name="bugzilla1">bug 1550804</a> a <a data-l10n-name="bugzilla2">bug 1137699</a> am fwy o fanylion.
+experimental-features-devtools-execution-context-selector =
+    .label = Developer Tools: Execution Context Selector
+experimental-features-devtools-execution-context-selector-description = Mae'r nodwedd hon yn dangos botwm ar linell orchymyn y consol sy'n caniatáu i chi newid y cyd-destun y gweithredir yr ymadrodd a nodwch ynddo. Gweler <a data-l10n-name="bugzilla1">bug 1605154</a> a <a data-l10n-name="bugzilla2">bug 1605153</a> am fwy o fanylion.
+experimental-features-devtools-compatibility-panel =
+    .label = Developer Tools: Compatibility Panel
+experimental-features-devtools-compatibility-panel-description = Panel ochr ar gyfer yr Arolygydd Tudalen sy'n dangos gwybodaeth i chi sy'n manylu ar statws cydnawsedd traws-borwr eich ap. Gweler <a data-l10n-name="bugzilla">bug 1584464</a> am fwy o fanylion.
+# Do not translate 'SameSite', 'Lax' and 'None'.
+experimental-features-cookie-samesite-lax-by-default2 =
+    .label = Cwcis: SameSite=Lax by default
+experimental-features-cookie-samesite-lax-by-default2-description = Trin cwcis fel “SameSite = Lax” by default os nad oes priodoledd “SameSite” wedi'i nodi. Rhaid i ddatblygwyr ddewis y cyflwr cyfredol o ddefnydd anghyfyngedig trwy ddewis yn benodol “SameSite = None”.
+# Do not translate 'SameSite', 'Lax' and 'None'.
+experimental-features-cookie-samesite-none-requires-secure2 =
+    .label = Cwcis: mae SameSite=none angen priodoledd ddiogel
+experimental-features-cookie-samesite-none-requires-secure2-description = Mae cwcis â phriodoledd “SameSite=None” angen y briodoledd ddiogel. Mae'r nodwedd hon yn gofyn am “Cookies: SameSite=Lax by default”.
+# about:home should be kept in English, as it refers to the the URI for
+# the internal default home page.
+experimental-features-abouthome-startup-cache =
+    .label = about:home startup cache
+experimental-features-abouthome-startup-cache-description = Storfa ar gyfer y ddogfen gychwynnol about:home sy'n cael ei llwytho yn ragosodedig wrth gychwyn. Pwrpas y storfa yw gwella perfformiad cychwyn.
+experimental-features-print-preview-tab-modal =
+    .label = Ailgynllunio'r Rhagolwg Argraffu
+experimental-features-print-preview-tab-modal-description = Mae rhagolwg argraffu wedi'i ailgynllunio ac yn cynnig rhagolwg argraffu ar y macOS. Gall hyn o bosibl gyflwyno toriadau ac nid yw'n cynnwys yr holl osodiadau sy'n gysylltiedig ag argraffu. I gael mynediad at yr holl osodiadau sy'n gysylltiedig ag argraffu, dewiswch "Argraffu gan ddefnyddio deialog y system..." o fewn y panel Argraffu.
+# The title of the experiment should be kept in English as it may be referenced
+# by various online articles and is technical in nature.
+experimental-features-cookie-samesite-schemeful =
+    .label = Cookies: Schemeful SameSite
+experimental-features-cookie-samesite-schemeful-description = Trin cwcis o'r un parth, ond gyda gwahanol gynlluniau (e.e. http://example.com a https://example.com) fel traws-gwefan yn lle'r un wefan. Yn gwella diogelwch, ond o bosibl yn cyflwyno toriadau.
+# "Service Worker" is an API name and is usually not translated.
+experimental-features-devtools-serviceworker-debugger-support =
+    .label = Developer Tools: Service Worker debugging
+# "Service Worker" is an API name and is usually not translated.
+experimental-features-devtools-serviceworker-debugger-support-description = Yn galluogi cefnogaeth arbrofol i Weithwyr Gwasanaeth yn y panel Dadfygiwr. Efallai y bydd y nodwedd hon yn arafu'r Offer Datblygwr ac yn cynyddu'r defnydd o gof.
+# WebRTC global mute toggle controls
+experimental-features-webrtc-global-mute-toggles =
+    .label = Toglau Tewi WebRTC Cyffredinol
+experimental-features-webrtc-global-mute-toggles-description = Ychwanegwch ffyrdd o reoli dangosydd rhannu WebRTC i gyd sy'n caniatáu i ddefnyddwyr dewi eu llif meicroffon a chamera.
+# JS JIT Warp project
+experimental-features-js-warp =
+    .label = JavaScript JIT: Warp
+experimental-features-js-warp-description = Galluogi Warp, project i wella perfformiad JavaScript a defnydd o'r cof.
+# Fission is the name of the feature and should not be translated.
+experimental-features-fission =
+    .label = Fission (Ynysu Gwefan)
+experimental-features-fission-description = Mae Fission (ynysu gwefan) yn nodwedd arbrofol yn { -brand-short-name } er mwyn darparu haen ychwanegol o ddiogelwch yn erbyn bygiau diogelwch. Trwy ynysu pob gwefan i broses ar wahân, mae Fission yn ei gwneud hi'n anoddach i wefannau maleisus gael mynediad at wybodaeth o dudalennau eraill rydych chi'n ymweld â nhw. Mae hwn yn newid pensaernïol mawr yn { -brand-short-name } ac rydym yn gwerthfawrogi eich bod yn profi ac yn adrodd am unrhyw faterion y gallech ddod ar eu traws. Am fwy o fanylion, darllenwch <a data-l10n-name="wiki">y wiki</a>.
+# Support for having multiple Picture-in-Picture windows open simultaneously
+experimental-features-multi-pip =
+    .label = Cefnogaeth Llun-mewn-Llun Lluosog
+experimental-features-multi-pip-description = Cefnogaeth arbrofol i ganiatáu i nifer o ffenestri Llun-mewn-Llun fod ar agor ar yr un pryd.
+experimental-features-http3 =
+    .label = Protocol HTTP/3
+experimental-features-http3-description = Cefnogaeth arbrofol i brotocol HTTP/3.
+# Search during IME
+experimental-features-ime-search =
+    .label = Bar Cyfeiriadau: dangos canlyniadau wrth ddefnyddio'r IME
+experimental-features-ime-search-description = Offeryn yw IME (Golygydd Dull Mewnbwn) sy'n eich galluogi i nodi symbolau cymhleth, fel y rhai sy'n cael eu ddefnyddio mewn ieithoedd ysgrifenedig yn Nwyrain Asia neu India, gan ddefnyddio bysellfwrdd safonol. Bydd galluogi'r arbrawf hwn yn cadw'r panel bar cyfeiriadau ar agor, dangos canlyniadau chwilio ac awgrymiadau, tra'n defnyddio IME i fewnbynnu testun. Sylwch y gallai'r IME ddangos panel sy'n ymdrin â chanlyniadau'r bar cyfeiriad, felly mae'r dewis hwn yn cael ei awgrymu ar gyfer IME sydd ddim yn defnyddio'r math hwn o banel.
diff --git a/l10n-cy/toolkit/toolkit/global/createProfileWizard.ftl b/l10n-cy/toolkit/toolkit/global/createProfileWizard.ftl
new file mode 100644
index 0000000000..36e13010b0
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/global/createProfileWizard.ftl
@@ -0,0 +1,53 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+create-profile-window =
+    .title = Creu Proffil Dewin
+    .style = width: 45em; height: 32em;
+
+## First wizard page
+
+create-profile-first-page-header =
+    { PLATFORM() ->
+        [macos] Cyflwyniad
+       *[other] Croeso i { create-profile-window.title }
+    }
+
+profile-creation-explanation-1 = Mae { -brand-short-name } yn storio gwybodaeth am eich gosodiadau a'ch dewisiadau yn eich proffil personol.
+
+profile-creation-explanation-2 = Os ydych yn rhannu'r copi o { -brand-short-name } gyda defnyddwyr eraill, mae modd defnyddio proffiliau i gadw gwybodaeth eich gilydd ar wahân. I wneud hyn, dylai pob defnyddiwr greu ei broffil ei hun.
+
+profile-creation-explanation-3 = Os mai chi yw'r unig berson sy'n defnyddio'r copi o { -brand-short-name }, rhaid i chi gael o leiaf un proffil. Os hoffech chi mae modd creu proffiliau niferus er mwyn cadw gosodiadau a dewisiadau i chi eich hun. Er enghraifft, efallai yr hoffech chi gael proffil gwahanol ar gyfer defnydd busnes neu bersonol.
+
+profile-creation-explanation-4 =
+    { PLATFORM() ->
+        [macos] I gychwyn creu eich proffil, cliciwch Ymlaen.
+       *[other] I gychwyn creu eich proffil, cliciwch Nesaf.
+    }
+
+## Second wizard page
+
+create-profile-last-page-header =
+    { PLATFORM() ->
+        [macos] Diweddglo
+       *[other] Cwblhau { create-profile-window.title }
+    }
+
+profile-creation-intro = Os ydych yn creu nifer o broffiliau mae modd eu gwahaniaethu wrth enw'r proffil. Mae modd defnyddio'r enw sy'n cael ei ddarparu yma neu enw eich hun.
+
+profile-prompt = Rhowch enw proffil newydd:
+    .accesskey = e
+
+profile-default-name =
+    .value = Defnyddiwr Rhagosodedig
+
+profile-directory-explanation = Bydd eich gosodiadau defnyddiwr, dewisiadau a data arall sy'n perthyn i ddefnyddiwr yn cael ei gadw yn:
+
+create-profile-choose-folder =
+    .label = Dewis Ffolder…
+    .accesskey = D
+
+create-profile-use-default =
+    .label = Defnyddio'r Ffolder Rhagosodedig
+    .accesskey = R
diff --git a/l10n-cy/toolkit/toolkit/global/handlerDialog.ftl b/l10n-cy/toolkit/toolkit/global/handlerDialog.ftl
new file mode 100644
index 0000000000..0a6266044c
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/global/handlerDialog.ftl
@@ -0,0 +1,69 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# Please keep the emphasis around the hostname and scheme (ie the
+# `<strong>` HTML tags). Please also keep the hostname as close to the start
+# of the sentence as your language's grammar allows.
+#
+# Variables:
+#  $host - the hostname that is initiating the request
+#  $scheme - the type of link that's being opened.
+handler-dialog-host = Mae <strong>{ $host }</strong> eisiau agor dolen <strong>{ $scheme }</strong>.
+
+## Permission Dialog
+## Variables:
+##  $host - the hostname that is initiating the request
+##  $scheme - the type of link that's being opened.
+##  $appName - Name of the application that will be opened.
+
+permission-dialog-description = Caniatáu i'r wefan hon agor y ddolen { $scheme }?
+permission-dialog-description-file = Caniatáu i'r ffeil hon agor y ddolen { $scheme }?
+permission-dialog-description-host = Caniatáu i { $host } agor y ddolen { $scheme }?
+permission-dialog-description-app = Caniatáu i'r wefan hon agor y ddolen { $scheme } gyda { $appName }?
+permission-dialog-description-host-app = Caniatáu i { $host } agor y ddolen { $scheme } gyda { $appName }?
+permission-dialog-description-file-app = Caniatáu i'r ffeil hon agor y ddolen { $scheme } gyda { $appName }?
+
+## Please keep the emphasis around the hostname and scheme (ie the
+## `<strong>` HTML tags). Please also keep the hostname as close to the start
+## of the sentence as your language's grammar allows.
+
+permission-dialog-remember = Caniatáu i <strong>{ $host }</strong> agor dolenni <strong>{ $scheme }</strong> bob tro
+permission-dialog-remember-file = Gadewch i'r ffeil hon agor dolenni <strong>{ $scheme }</strong> bob tro
+
+##
+
+permission-dialog-btn-open-link =
+    .label = Agor Dolen
+    .accessKey = A
+permission-dialog-btn-choose-app =
+    .label = Dewis Rhaglen
+    .accessKey = R
+permission-dialog-unset-description = Bydd angen i chi ddewis rhaglen.
+permission-dialog-set-change-app-link = Dewiswch raglen arall.
+
+## Chooser dialog
+## Variables:
+##  $scheme - the type of link that's being opened.
+
+chooser-window =
+    .title = Dewis Rhaglen
+    .style = min-width: 26em; min-height: 26em;
+chooser-dialog =
+    .buttonlabelaccept = Agor Dolen
+    .buttonaccesskeyaccept = A
+chooser-dialog-description = Dewiswch raglen i agor y ddolen { $scheme }.
+# Please keep the emphasis around the scheme (ie the `<strong>` HTML tags).
+chooser-dialog-remember = Defnyddiwch y rhaglen hon i agor dolenni <strong>{ $scheme }</strong> bob tro
+chooser-dialog-remember-extra =
+    { PLATFORM() ->
+        [windows] Mae modd newid hwn yn newisiadau { -brand-short-name }.
+       *[other] Mae modd newid hwn yn newisiadau { -brand-short-name }.
+    }
+choose-other-app-description = Dewis Rhaglen arall
+choose-app-btn =
+    .label = Dewis…
+    .accessKey = D
+choose-other-app-window-title = Rhaglen Arall…
+# Displayed under the name of a protocol handler in the Launch Application dialog.
+choose-dialog-privatebrowsing-disabled = Analluogwyd mewn Ffenestri Preifat
diff --git a/l10n-cy/toolkit/toolkit/global/processTypes.ftl b/l10n-cy/toolkit/toolkit/global/processTypes.ftl
new file mode 100644
index 0000000000..a553d09c4f
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/global/processTypes.ftl
@@ -0,0 +1,36 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+process-type-web = Cynnwys Gwe
+
+# process used to run privileged about pages,
+# such as about:home
+process-type-privilegedabout = About Breintiedig
+
+# process used to run privileged mozilla pages,
+# such as accounts.firefox.com
+process-type-privilegedmozilla = Cynnwys Mozilla Breintiedig
+
+process-type-extension = Estyniad
+
+# process used to open file:// URLs
+process-type-file = Ffeil Leol
+
+# process used to isolate webpages that requested special
+# permission to allocate large amounts of memory
+process-type-weblargeallocation = Dyraniad Mawr
+
+# process used to isolate a webpage from other web pages
+# to improve security
+process-type-webisolated = Cynnwys Gwe Ynysig
+
+# process used to communicate with the GPU for
+# graphics acceleration
+process-type-gpu = GPU
+
+# process used to perform network operations
+process-type-socket = Soced
+
+# process preallocated; may change to other types
+process-type-prealloc = Rhagddyranwyd
diff --git a/l10n-cy/toolkit/toolkit/global/profileDowngrade.ftl b/l10n-cy/toolkit/toolkit/global/profileDowngrade.ftl
new file mode 100644
index 0000000000..53c4d418c4
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/global/profileDowngrade.ftl
@@ -0,0 +1,20 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+profiledowngrade-window =
+    .title = Rydych chi wedi cychwyn fersiwn hŷn o { -brand-product-name }
+    .style = width: 490px;
+
+profiledowngrade-window-create =
+    .label = Creu Proffil Newydd
+
+profiledowngrade-sync = Mae defnyddio fersiwn hŷn o { -brand-product-name } yn gallu llygru nodiadau llyfr a hanes pori sydd eisoes wedi'u cadw i broffil { -brand-product-name } presennol. Er mwyn diogelu'ch gwybodaeth, crëwch broffil newydd ar gyfer gosodiad hwn o { -brand-short-name }. Gallwch fewngofnodi gyda { -fxaccount-brand-name } i gydweddu eich nodau tudalen a'ch hanes pori rhwng proffiliau.
+profiledowngrade-nosync = Mae defnyddio fersiwn hŷn o { -brand-product-name } yn gallu llygru nodau tudalen a hanes pori sydd eisoes wedi'u cadw i broffil { -brand-product-name } presennol. Er mwyn diogelu'ch gwybodaeth, crëwch broffil newydd ar gyfer gosod { -brand-short-name }.
+
+profiledowngrade-quit =
+    .label =
+        { PLATFORM() ->
+            [windows] Gadael
+           *[other] Gadael
+        }
diff --git a/l10n-cy/toolkit/toolkit/global/profileSelection.ftl b/l10n-cy/toolkit/toolkit/global/profileSelection.ftl
new file mode 100644
index 0000000000..5616e2655b
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/global/profileSelection.ftl
@@ -0,0 +1,36 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+profile-selection-window =
+    .title = { -brand-short-name } - Dewiswch Broffil Defnyddiwr
+
+profile-selection-button-accept =
+    .label = Cychwyn { -brand-short-name }
+
+profile-selection-button-cancel =
+    .label = Gadael
+
+profile-selection-new-button =
+    .label = Creu Proffil…
+    .accesskey = C
+
+profile-selection-rename-button =
+    .label = Ailenwi Profil…
+    .accesskey = r
+
+profile-selection-delete-button =
+    .label = Dileu Proffil…
+    .accesskey = D
+
+## Messages used in the profile manager
+
+profile-manager-description = Mae { -brand-short-name } yn storio gwybodaeth am eich gosodiadau, dewisiadau ac eitemau defnyddiwr arall yn eich proffil defnyddiwr.
+
+profile-manager-work-offline =
+    .label = Gweithio All-lein
+    .accesskey = o
+
+profile-manager-use-selected =
+    .label = Defnyddio'r proffil penodol heb ofyn wrth gychwyn
+    .accesskey = p
diff --git a/l10n-cy/toolkit/toolkit/global/resetProfile.ftl b/l10n-cy/toolkit/toolkit/global/resetProfile.ftl
new file mode 100644
index 0000000000..5cbc72b5a9
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/global/resetProfile.ftl
@@ -0,0 +1,14 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+refresh-profile-dialog =
+    .title = Adnewyddu { -brand-short-name }
+refresh-profile-dialog-button =
+    .label = Adnewyddu { -brand-short-name }
+refresh-profile-description = Cychwyn o'r newydd i ddatrys problemau ac adfer perfformiad.
+refresh-profile-description-details = Bydd hyn yn:
+refresh-profile-remove = Tynnu eich ychwanegion a'ch cyfaddasiadau
+refresh-profile-restore = Adfer eich gosodiadau pori i'w rhagosodiad
+refresh-profile = Rhoi bywyd newydd i { -brand-short-name }
+refresh-profile-button = Adnewyddu { -brand-short-name }…
diff --git a/l10n-cy/toolkit/toolkit/global/textActions.ftl b/l10n-cy/toolkit/toolkit/global/textActions.ftl
new file mode 100644
index 0000000000..3d7e4d19da
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/global/textActions.ftl
@@ -0,0 +1,49 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+text-action-undo =
+    .label = Dadwneud
+    .accesskey = w
+
+text-action-undo-shortcut =
+    .key = Z
+
+text-action-redo =
+    .label = Ailwneud
+    .accesskey = A
+
+text-action-redo-shortcut =
+    .key = Y
+
+text-action-cut =
+    .label = Torri
+    .accesskey = T
+
+text-action-cut-shortcut =
+    .key = X
+
+text-action-copy =
+    .label = Copïo
+    .accesskey = C
+
+text-action-copy-shortcut =
+    .key = C
+
+text-action-paste =
+    .label = Gludo
+    .accesskey = G
+
+text-action-paste-shortcut =
+    .key = V
+
+text-action-delete =
+    .label = Dileu
+    .accesskey = i
+
+text-action-select-all =
+    .label = Dewis Popeth
+    .accesskey = P
+
+text-action-select-all-shortcut =
+    .key = A
diff --git a/l10n-cy/toolkit/toolkit/global/unknownContentType.ftl b/l10n-cy/toolkit/toolkit/global/unknownContentType.ftl
new file mode 100644
index 0000000000..50d6dd99df
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/global/unknownContentType.ftl
@@ -0,0 +1,13 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+unknowncontenttype-handleinternally =
+    .label = Agor gyda { -brand-short-name }
+    .accesskey = A
+unknowncontenttype-settingschange =
+    .value =
+        { PLATFORM() ->
+            [windows] Mae modd newid gosodiadau yn Opsiynau { -brand-short-name }.
+           *[other] Mae modd newid gosodiadau yn Dewisiadau { -brand-short-name }.
+        }
diff --git a/l10n-cy/toolkit/toolkit/global/videocontrols.ftl b/l10n-cy/toolkit/toolkit/global/videocontrols.ftl
new file mode 100644
index 0000000000..79aa378803
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/global/videocontrols.ftl
@@ -0,0 +1,14 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+videocontrols-scrubber =
+    .aria-label = Safle
+# This label is used by screenreaders and other assistive technology to indicate
+# to users how much of the video has been loaded from the network. It will be
+# followed by the percentage of the video that has loaded (e.g. "Loading: 13%").
+videocontrols-buffer-bar-label = Llwytho:
+videocontrols-volume-control =
+    .aria-label = Lefel y sain
+videocontrols-closed-caption-button =
+    .aria-label = Capsiynau Caeedig
diff --git a/l10n-cy/toolkit/toolkit/global/wizard.ftl b/l10n-cy/toolkit/toolkit/global/wizard.ftl
new file mode 100644
index 0000000000..3f50113b90
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/global/wizard.ftl
@@ -0,0 +1,37 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+wizard-macos-button-back =
+    .label = Mynd Nôl
+    .accesskey = N
+wizard-linux-button-back =
+    .label = Nôl
+    .accesskey = N
+wizard-win-button-back =
+    .label = < Nôl
+    .accesskey = l
+
+wizard-macos-button-next =
+    .label = Ymlaen
+    .accesskey = Y
+wizard-linux-button-next =
+    .label = Nesaf
+    .accesskey = e
+wizard-win-button-next =
+    .label = Nesaf >
+    .accesskey = e
+
+wizard-macos-button-finish =
+    .label = Gorffen
+wizard-linux-button-finish =
+    .label = Gorffen
+wizard-win-button-finish =
+    .label = Gorffen
+
+wizard-macos-button-cancel =
+    .label = Diddymu
+wizard-linux-button-cancel =
+    .label = Diddymu
+wizard-win-button-cancel =
+    .label = Diddymu
diff --git a/l10n-cy/toolkit/toolkit/intl/languageNames.ftl b/l10n-cy/toolkit/toolkit/intl/languageNames.ftl
new file mode 100644
index 0000000000..f21c385cf2
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/intl/languageNames.ftl
@@ -0,0 +1,212 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+language-name-aa = Afar
+language-name-ab = Abcasaidd
+language-name-ach = Acholi
+language-name-ae = Avestan
+language-name-af = Affricaneg
+language-name-ak = Akan
+language-name-am = Amhareg
+language-name-an = Aragoneg
+language-name-ar = Arabeg
+language-name-as = Assameje
+language-name-ast = Asturieg
+language-name-av = Avareg
+language-name-ay = Aymara
+language-name-az = Azereg
+language-name-ba = Bashkir
+language-name-be = Belorwseg
+language-name-bg = Bwlgareg
+language-name-bh = Bihari
+language-name-bi = Bislameg
+language-name-bm = Bambara
+language-name-bn = Bengaleg
+language-name-bo = Tibet
+language-name-br = Llydaweg
+language-name-bs = Bosniaeg
+language-name-ca = Catalaneg
+language-name-cak = Kaqchikel
+language-name-ce = Chechen
+language-name-ch = Chamorro
+language-name-co = Corseg
+language-name-cr = Cree
+language-name-crh = Tatar Crimea
+language-name-cs = Tsieceg
+language-name-csb = Kashubian
+language-name-cu = Slafeg Eglwysig
+language-name-cv = Chuvash
+language-name-cy = Cymraeg
+language-name-da = Daeneg
+language-name-de = Almaeneg
+language-name-dsb = Sorbieg Isaf
+language-name-dv = Divehi
+language-name-dz = Dzongkha
+language-name-ee = Ewe
+language-name-el = Groeg
+language-name-en = Saesneg
+language-name-eo = Esperanto
+language-name-es = Sbaeneg
+language-name-et = Estoneg
+language-name-eu = Basgeg
+language-name-fa = Persieg
+language-name-ff = Fulah
+language-name-fi = Ffineg
+language-name-fj = Fijieg
+language-name-fo = Ffaroeg
+language-name-fr = Ffrangeg
+language-name-fur = Ffriulieg
+language-name-fy = Frisieg
+language-name-ga = Gwyddeleg
+language-name-gd = Gaeleg yr Alban
+language-name-gl = Galiseg
+language-name-gn = Gwarani
+language-name-gu = Gwjarati
+language-name-gv = Manaweg
+language-name-ha = Hawsa
+language-name-haw = Hawaieg
+language-name-he = Hebraeg
+language-name-hi = Hindi
+language-name-hil = Hiligaynon
+language-name-ho = Hiri Motu
+language-name-hr = Croateg
+language-name-hsb = Sorbieg Uchaf
+language-name-ht = Haiteg
+language-name-hu = Hwngareg
+language-name-hy = Armeneg
+language-name-hz = Herero
+language-name-ia = Interlingua
+language-name-id = Indonesieg
+language-name-ie = Interlingue
+language-name-ig = Igbo
+language-name-ii = Sichuan Yi
+language-name-ik = Inupiaq
+language-name-io = Ido
+language-name-is = Islandeg
+language-name-it = Eidaleg
+language-name-iu = Inuktitut
+language-name-ja = Siapanaëeg
+language-name-jv = Java
+language-name-ka = Georgeg
+language-name-kab = Kabyle
+language-name-kg = Kongo
+language-name-ki = Kikuyu
+language-name-kj = Kuanyama
+language-name-kk = Kazakh
+language-name-kl = Esgimoeg
+language-name-km = Khmer
+language-name-kn = Canareg
+language-name-ko = Coreeg
+language-name-kok = Konkani
+language-name-kr = Kanuri
+language-name-ks = Kashmir
+language-name-ku = Kwrdeg
+language-name-kv = Komi
+language-name-kw = Cernyweg
+language-name-ky = Kighiz
+language-name-la = Lladin
+language-name-lb = Luxembourgeg
+language-name-lg = Ganda
+language-name-li = Limburgeg
+language-name-lij = Ligurieg
+language-name-ln = Lingala
+language-name-lo = Lao
+language-name-lt = Lithwaneg
+language-name-ltg = Latgalieg
+language-name-lu = Luba-Katanga
+language-name-lv = Latfieg
+language-name-mai = Maithili
+language-name-meh = Tlaxiaco Mixtec y De Orllewin
+language-name-mg = Malagasy
+language-name-mh = Marshalleg
+language-name-mi = Maori
+language-name-mix = Mixtepec Mixtec
+language-name-mk = Macedoneg
+language-name-ml = Malaialam
+language-name-mn = Mongoleg
+language-name-mr = Marathi
+language-name-ms = Malaisieg
+language-name-mt = Malteg
+language-name-my = Byrmaneg
+language-name-na = Nauru
+language-name-nb = Norwyeg Bokmaal
+language-name-nd = Ndebele Gogleddol
+language-name-ne = Nepalieg
+language-name-ng = Ndonga
+language-name-nl = Iseldireg
+language-name-nn = Norwyeg Nynorsk
+language-name-no = Norwyeg
+language-name-nr = Ndebele Deheuol
+language-name-nso = Sotho Gogleddol
+language-name-nv = Navajo
+language-name-ny = Chichewa
+language-name-oc = Occitaneg
+language-name-oj = Ojibwa
+language-name-om = Oromo
+language-name-or = Odia
+language-name-os = Ossetian
+language-name-pa = Punjabeg
+language-name-pi = Pali
+language-name-pl = Pwyleg
+language-name-ps = Pashto
+language-name-pt = Portiwgaleg
+language-name-qu = Quechua
+language-name-rm = Rheto-Romaneg
+language-name-rn = Kirundi
+language-name-ro = Rwmaneg
+language-name-ru = Rwseg
+language-name-rw = Kinyarwanda
+language-name-sa = Sansgrit
+language-name-sc = Sardinieg
+language-name-sd = Sindhi
+language-name-se = Sami Gogleddol
+language-name-sg = Sango
+language-name-si = Singhaleg
+language-name-sk = Slofacieg
+language-name-sl = Slofeneg
+language-name-sm = Samoeg
+language-name-sn = Shona
+language-name-so = Somali
+language-name-son = Songhay
+language-name-sq = Albaneg
+language-name-sr = Serbeg
+language-name-ss = Siswati
+language-name-st = Sotho Deheuol
+language-name-su = Sundaneg
+language-name-sv = Swedeg
+language-name-sw = Swahili
+language-name-ta = Tamileg
+language-name-te = Telugu
+language-name-tg = Tajik
+language-name-th = Tai
+language-name-ti = Tigrinya
+language-name-tig = Tigre
+language-name-tk = Turkmen
+language-name-tl = Tagalog
+language-name-tlh = Klingon
+language-name-tn = Tswana
+language-name-to = Tonga
+language-name-tr = Twrceg
+language-name-trs = Triqui
+language-name-ts = Tsonga
+language-name-tt = Tatar
+language-name-tw = Twi
+language-name-ty = Tahiteg
+language-name-ug = Uighur
+language-name-uk = Wcraneg
+language-name-ur = Wrdw
+language-name-uz = Wsbeceg
+language-name-ve = Venda
+language-name-vi = Fietnameg
+language-name-vo = Volapük
+language-name-wa = Walloon
+language-name-wen = Sorbeg
+language-name-wo = Wolof
+language-name-xh = Xhosa
+language-name-yi = Iddeweg
+language-name-yo = Yoruba
+language-name-za = Zhuang
+language-name-zam = Miahuatlán Zapotec
+language-name-zh = Tsieinëeg
+language-name-zu = Zwlweg
diff --git a/l10n-cy/toolkit/toolkit/intl/regionNames.ftl b/l10n-cy/toolkit/toolkit/intl/regionNames.ftl
new file mode 100644
index 0000000000..149aa85aff
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/intl/regionNames.ftl
@@ -0,0 +1,280 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+### Notice: If you're updating this list, you should also
+###         update the list in mozIntl.js.
+
+region-name-ad = Andorra
+region-name-ae = United Arab Emirates
+region-name-af = Afghanistan
+region-name-ag = Antigua a Barbuda
+region-name-ai = Anguilla
+region-name-al = Albania
+region-name-am = Armenia
+region-name-ao = Angola
+region-name-aq = Antarctica
+region-name-ar = Ariannin
+region-name-as = Samoa Americanaidd
+region-name-at = Awstria
+region-name-au = Awstralia
+region-name-aw = Aruba
+region-name-az = Azerbaijan
+region-name-ba = Bosnia a Herzegovina
+region-name-bb = Barbados
+region-name-bd = Bangladesh
+region-name-be = Gwlad Belg
+region-name-bf = Burkina Faso
+region-name-bg = Bwlgaria
+region-name-bh = Bahrain
+region-name-bi = Burundi
+region-name-bj = Benin
+region-name-bl = Saint Barthélemy
+region-name-bm = Bermuda
+region-name-bn = Brunei
+region-name-bo = Bolivia
+region-name-bq = Bonaire, Sint Eustatius, a Saba
+region-name-br = Brasil
+region-name-bs = Bahamas
+region-name-bt = Bhutan
+region-name-bv = Ynys Bouvet
+region-name-bw = Botswana
+region-name-by = Belarus
+region-name-bz = Belize
+region-name-ca = Canada
+region-name-cc = Ynysoedd Cocos (Keeling)
+region-name-cd = Congo (Kinshasa)
+region-name-cf = Gweriniaeth Affricanaidd Congo
+region-name-cg = Congo (Brazzaville)
+region-name-ch = Y Swistir
+region-name-ci = Côte d’Ivoire
+region-name-ck = Ynysoedd Cook
+region-name-cl = Chile
+region-name-cm = Cameroon
+region-name-cn = Tsieina
+region-name-co = Colombia
+region-name-cp = Ynys Clipperton
+region-name-cr = Costa Rica
+region-name-cu = Ciwba
+region-name-cv = Cape Verde
+region-name-cw = Curaçao
+region-name-cx = Ynys Christmas
+region-name-cy = Cyprus
+region-name-cz = Gweriniaeth Tsiec
+region-name-de = Yr Almaen
+region-name-dg = Diego Garcia
+region-name-dj = Djibouti
+region-name-dk = Denmarc
+region-name-dm = Dominica
+region-name-do = Gweriniaeth Dominica
+region-name-dz = Algeria
+region-name-ec = Ecuador
+region-name-ee = Estonia
+region-name-eg = Yr Aifft
+region-name-eh = Gorllenwin Sahara
+region-name-er = Eritrea
+region-name-es = Sbaen
+region-name-et = Ethiopia
+region-name-fi = Ffindir
+region-name-fj = Ffiji
+region-name-fk = Ynysoedd Malfinas (Falkland)
+region-name-fm = Micronesia, Federated States of
+region-name-fo = Ynysoedd Ffaroe
+region-name-fr = Ffrainc
+region-name-ga = Gabon
+region-name-gb = Y Deyrnas Unedig
+region-name-gd = Grenada
+region-name-ge = Georgia
+region-name-gf = Guiana Ffrengig
+region-name-gg = Guernsey
+region-name-gh = Ghana
+region-name-gi = Gibraltar
+region-name-gl = Greenland
+region-name-gm = Gambia
+region-name-gn = Guinea
+region-name-gp = Guadeloupe
+region-name-gq = Guinea Cyhydeddol
+region-name-gr = Groeg
+region-name-gs = De Georgia ac Ynysoedd De Sandwich
+region-name-gt = Guatemala
+region-name-gu = Guam
+region-name-gw = Guinea-Bissau
+region-name-gy = Guyana
+region-name-hk = Hong Kong
+region-name-hm = Ynys Heard ac Ynys McDonald
+region-name-hn = Honduras
+region-name-hr = Croatia
+region-name-ht = Haiti
+region-name-hu = Hwngari
+region-name-id = Indonesia
+region-name-ie = Iwerddon
+region-name-il = Israel
+region-name-im = Ynys Manaw
+region-name-in = India
+region-name-io = Tiriogaeth Cefnfor Indiaidd Prydain
+region-name-iq = Irac
+region-name-ir = Iran
+region-name-is = Ynys yr Iâ
+region-name-it = Yr Eidal
+region-name-je = Jersey
+region-name-jm = Jamaica
+region-name-jo = Yr Iorddonen
+region-name-jp = Siapan
+region-name-ke = Kenya
+region-name-kg = Kyrgyzstan
+region-name-kh = Cambodia
+region-name-ki = Kiribati
+region-name-km = Comoros
+region-name-kn = Saint Kitts a Nevis
+region-name-kp = Corea, Gogledd
+region-name-kr = Corea, De
+region-name-kw = Kuwait
+region-name-ky = Ynysoedd Cayman
+region-name-kz = Kazakhstan
+region-name-la = Laos
+region-name-lb = Libanus
+region-name-lc = Saint Lucia
+region-name-li = Luxembourg
+region-name-lk = Sri Lanka
+region-name-lr = Liberia
+region-name-ls = Lesotho
+region-name-lt = Lithiwania
+region-name-lu = Liechtenstein
+region-name-lv = Latfia
+region-name-ly = Libya
+region-name-ma = Morocco
+region-name-mc = Monaco
+region-name-md = Moldova
+region-name-me = Montenegro
+region-name-mf = Saint Martin
+region-name-mg = Madagascar
+region-name-mh = Ynysoedd Marshall
+region-name-mk = Macedonia
+region-name-ml = Mali
+region-name-mm = Burma
+region-name-mn = Mongolia
+region-name-mo = Macau
+region-name-mp = Ynysoedd Gogledd Mariana
+region-name-mq = Martinique
+region-name-mr = Mauritania
+region-name-ms = Montserrat
+region-name-mt = Malta
+region-name-mu = Mauritius
+region-name-mv = Maldives
+region-name-mw = Malawi
+region-name-mx = Mecsico
+region-name-my = Malaysia
+region-name-mz = Mozambique
+region-name-na = Namibia
+region-name-nc = Caledonia Newydd
+region-name-ne = Niger
+region-name-nf = Ynys Norfolk
+region-name-ng = Nigeria
+region-name-ni = Nicaragua
+region-name-nl = Yr Iseldiroedd
+region-name-no = Norwy
+region-name-np = Nepal
+region-name-nr = Nauru
+region-name-nu = Niue
+region-name-nz = Seland Newydd
+region-name-om = Oman
+region-name-pa = Panama
+region-name-pe = Periw
+region-name-pf = Polynesia Ffrengig
+region-name-pg = Papua Guinea Newydd
+region-name-ph = Philippines
+region-name-pk = Pacistan
+region-name-pl = Gwlad Pwyl
+region-name-pm = Saint Pierre a Miquelon
+region-name-pn = Ynysoedd Pitcairn
+region-name-pr = Puerto Rico
+region-name-pt = Portiwgal
+region-name-pw = Palau
+region-name-py = Paraguay
+region-name-qa = Qatar
+region-name-qm = Ynysoedd Midway
+region-name-qs = Bassas da India
+region-name-qu = Ynys Juan de Nova
+region-name-qw = Ynys Wake
+region-name-qx = Ynysoedd Glorioso
+region-name-qz = Akrotiri
+region-name-re = Reunion
+region-name-ro = Rwmania
+region-name-rs = Serbia
+region-name-ru = Rwsia
+region-name-rw = Rwanda
+region-name-sa = Saudi Arabia
+region-name-sb = Ynysoedd Solomon
+region-name-sc = Seychelles
+region-name-sd = Swdan
+region-name-se = Sweden
+region-name-sg = Singapore
+region-name-sh = Saint Helena, Ascension, a Tristan da Cunha
+region-name-si = Slofenia
+region-name-sk = Slofacia
+region-name-sl = Sierra Leone
+region-name-sm = San Marino
+region-name-sn = Senegal
+region-name-so = Somalia
+region-name-sr = Suriname
+region-name-ss = De Sudan
+region-name-st = Sao Tome a Principe
+region-name-sv = El Salvador
+region-name-sx = Sint Maarten
+region-name-sy = Syria
+region-name-sz = Swaziland
+region-name-tc = Ynysoedd Turks a Caicos
+region-name-td = Chad
+region-name-tf = Tiriogaethau De ac Antartic Ffrainc
+region-name-tg = Togo
+region-name-th = Thailand
+region-name-tj = Tajikistan
+region-name-tk = Tokelau
+region-name-tl = Timor-Leste
+region-name-tm = Turkmenistan
+region-name-tn = Tunisia
+region-name-to = Tonga
+region-name-tr = Twrci
+region-name-tt = Trinidad a Tobago
+region-name-tv = Tuvalu
+region-name-tw = Taiwan
+region-name-tz = Tanzania
+region-name-ua = Wcrain
+region-name-ug = Uganda
+region-name-us = Yr Unol Daleithiau
+region-name-uy = Uruguay
+region-name-uz = Uzbekistan
+region-name-va = Dinas y Fatican
+region-name-vc = Saint Vincent a'r Grenadinau
+region-name-ve = Venezuela
+region-name-vg = Ynysoedd Virgin Prydain
+region-name-vi = Ynysoedd Virgin, UDA.
+region-name-vn = Fietnam
+region-name-vu = Vanuatu
+region-name-wf = Wallis a Futuna
+region-name-ws = Samoa
+region-name-xa = Ynysoedd Ashmore a Cartier
+region-name-xb = Ynys Baker
+region-name-xc = Ynysoedd y Môr Cwrel
+region-name-xd = Dhekelia
+region-name-xe = Ynys Europa
+region-name-xg = Llain Gaza
+region-name-xh = Ynys Howland
+region-name-xj = Jan Mayen
+region-name-xk = Kosovo
+region-name-xl = Atol Palmyra
+region-name-xm = Riff Kingman
+region-name-xp = Ynysoedd Parasel
+region-name-xq = Ynys Jarvis
+region-name-xr = Svalbard
+region-name-xs = Ynysoedd Spratly
+region-name-xt = Ynys Tromelin
+region-name-xu = Atol Johnston
+region-name-xv = Ynys Navassa
+region-name-xw = Ardal Gorllewin
+region-name-ye = Yemen
+region-name-yt = Mayotte
+region-name-za = De Affrica
+region-name-zm = Zambia
+region-name-zw = Zimbabwe
diff --git a/l10n-cy/toolkit/toolkit/main-window/autocomplete.ftl b/l10n-cy/toolkit/toolkit/main-window/autocomplete.ftl
new file mode 100644
index 0000000000..3ab63f5cd2
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/main-window/autocomplete.ftl
@@ -0,0 +1,32 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+## Import Logins Autocomplete
+
+# Variables:
+#   $browser (String) - Browser name to import logins from.
+#   $host (String) - Host name of the current site.
+autocomplete-import-logins =
+    <div data-l10n-name="line1">Mewnforio eich data o { $browser }</div>
+    <div data-l10n-name="line2">ar gyfer { $host } a gwefannau eraill</div>
+autocomplete-import-logins-info =
+    .tooltiptext = Dysgu rhagor
+
+## Variables:
+##   $host (String) - Host name of the current site.
+
+autocomplete-import-logins-chrome =
+    <div data-l10n-name="line1">Mewnforio eich data o o Google Chrome </div>
+    <div data-l10n-name="line2">ar gyfer { $host } a gwefannau eraill</div>
+autocomplete-import-logins-chromium =
+    <div data-l10n-name="line1">Mewnforio eich mewngofnod o Chromium</div>
+    <div data-l10n-name="line2">ar gyfer { $host } a gwefannau eraill</div>
+autocomplete-import-logins-chromium-edge =
+    <div data-l10n-name="line1">Mewnforio eich mewngofnod o Microsoft Edge</div>
+    <div data-l10n-name="line2">ar gyfer { $host } a gwefannau eraill</div>
+
+##
+
+autocomplete-import-learn-more = Dysgu rhagor
diff --git a/l10n-cy/toolkit/toolkit/main-window/findbar.ftl b/l10n-cy/toolkit/toolkit/main-window/findbar.ftl
new file mode 100644
index 0000000000..66190490e1
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/main-window/findbar.ftl
@@ -0,0 +1,38 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+### This file contains the entities needed to use the Find Bar.
+
+findbar-next =
+    .tooltiptext = Canfod enghraifft nesaf yr ymadrodd
+findbar-previous =
+    .tooltiptext = Canfod enghraifft flaenorol o'r ymadrodd
+
+findbar-find-button-close =
+    .tooltiptext = Cau'r bar chwilio
+
+findbar-highlight-all2 =
+    .label = Amlygu Popeth
+    .accesskey =
+        { PLATFORM() ->
+            [macos] l
+           *[other] a
+        }
+    .tooltiptext = Amlygu pob enghraifft o'r ymadrodd
+
+findbar-case-sensitive =
+    .label = Cydweddu Maint
+    .accesskey = C
+    .tooltiptext = Chwilio gyda sensitifrwydd maint nodau
+
+findbar-match-diacritics =
+    .label = Diacritig cyfatebol
+    .accesskey = i
+    .tooltiptext = Gwahaniaethu rhwng nodau acennog a nodau sylfaenol, (e.e. wrth chwilio am “resume”, ni fydd “résumé” yn cael ei gynnig)
+
+findbar-entire-word =
+    .label = Geiriau Llawn
+    .accesskey = G
+    .tooltiptext = Chwilio'r geiriau llawn yn unig
diff --git a/l10n-cy/toolkit/toolkit/payments/payments.ftl b/l10n-cy/toolkit/toolkit/payments/payments.ftl
new file mode 100644
index 0000000000..826f443fb5
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/payments/payments.ftl
@@ -0,0 +1,69 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+# This value isn't used directly, but is defined to avoid duplication
+# in the "credit-card-label-*" strings.
+#
+# Variables:
+#   $month (String): Numeric month the credit card expires
+#   $year (String): Four-digit year the credit card expires
+credit-card-expiration = Yn dod i ben ar { $month }/{ $year }
+
+## These labels serve as a description of a credit card.
+## The description must include a credit card number, and may optionally
+## include a cardholder name, an expiration date, or both, so we have
+## four variations.
+
+# Label for a credit card with a number only
+#
+# Variables:
+#   $number (String): Partially-redacted credit card number
+credit-card-label-number = { $number }
+# Label for a credit card with a number and name
+#
+# Variables:
+#   $number (String): Partially-redacted credit card number
+#   $name (String): Cardholder name
+credit-card-label-number-name = { $number }, { $name }
+# Label for a credit card with a number and expiration date
+#
+# Variables:
+#   $number (String): Partially-redacted credit card number
+credit-card-label-number-expiration = { $number }, { credit-card-expiration }
+# Label for a credit card with a number, name, and expiration date
+#
+# Variables:
+#   $number (String): Partially-redacted credit card number
+#   $name (String): Cardholder name
+credit-card-label-number-name-expiration = { $number }, { $name }, { credit-card-expiration }
+# Label for a credit card with a number only
+#
+# Variables:
+#   $number (String): Partially-redacted credit card number
+#   $type (String): Credit card type
+credit-card-label-number-2 = { $number }
+    .aria-label = { $type } { credit-card-label-number-2 }
+# Label for a credit card with a number and name
+#
+# Variables:
+#   $number (String): Partially-redacted credit card number
+#   $name (String): Cardholder name
+#   $type (String): Credit card type
+credit-card-label-number-name-2 = { $number }, { $name }
+    .aria-label = { $type } { credit-card-label-number-name-2 }
+# Label for a credit card with a number and expiration date
+#
+# Variables:
+#   $number (String): Partially-redacted credit card number
+#   $type (String): Credit card type
+credit-card-label-number-expiration-2 = { $number }, { credit-card-expiration }
+    .aria-label = { $type } { credit-card-label-number-expiration-2 }
+# Label for a credit card with a number, name, and expiration date
+#
+# Variables:
+#   $number (String): Partially-redacted credit card number
+#   $name (String): Cardholder name
+#   $type (String): Credit card type
+credit-card-label-number-name-expiration-2 = { $number }, { $name }, { credit-card-expiration }
+    .aria-label = { $type } { credit-card-label-number-name-expiration-2 }
diff --git a/l10n-cy/toolkit/toolkit/pictureinpicture/pictureinpicture.ftl b/l10n-cy/toolkit/toolkit/pictureinpicture/pictureinpicture.ftl
new file mode 100644
index 0000000000..274f38a3df
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/pictureinpicture/pictureinpicture.ftl
@@ -0,0 +1,22 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+pictureinpicture-player-title = Llun mewn Llun
+
+pictureinpicture-pause =
+    .aria-label = Oedi
+pictureinpicture-play =
+    .aria-label = Chwarae
+
+pictureinpicture-mute =
+    .aria-label = Tewi
+pictureinpicture-unmute =
+    .aria-label = Dad dewi
+
+pictureinpicture-unpip =
+    .aria-label = Anfon nôl i'r tab
+
+pictureinpicture-close =
+    .aria-label = Cau
+
diff --git a/l10n-cy/toolkit/toolkit/preferences/preferences.ftl b/l10n-cy/toolkit/toolkit/preferences/preferences.ftl
new file mode 100644
index 0000000000..9eabe33060
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/preferences/preferences.ftl
@@ -0,0 +1,61 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+password-not-set =
+    .value = (heb ei osod)
+
+failed-pw-change = Methu newid y Prif Gyfrinair.
+incorrect-pw = Wedi rhoi cyfrinair anghywir. Ceisiwch eto.
+pw-change-ok = Newidiwyd y Prif Gyfrinair yn llwyddiannus.
+
+pw-empty-warning = Ni fydd eich cyfrineiriau gwe ac e-bost, data ffurflen, nag eich allweddi preifat yn cael eu hamddiffyn.
+pw-erased-ok = Rydych wedi dileu eich Prif Gyfrinair.  { pw-empty-warning }
+pw-not-wanted = Rhybudd! Rydych wedi penderfynu peidio defnyddio Prif Gyfrinair. { pw-empty-warning }
+
+pw-change2empty-in-fips-mode = Rydych ym modd FIPS. Mae FIPS angen Prif Gyfrinair nad yw'n wag.
+
+failed-pp-change = Methu newid y Prif Gyfrinair.
+incorrect-pp = Nid ydych wedi rhoi'r Prif Gyfrinair cyfredol cywir. Ceisiwch eto.
+pp-change-ok = Mae'r Prif Gyfrinair wedi ei newid yn llwyddiannus.
+
+pp-empty-warning = Fydd eich cyfrineiriau a'ch allweddi preifat wedi'u storio ddim yn cael eu gwarchod.
+pp-erased-ok = Rydych wedi dileu eich Prif Gyfrinair.  { pp-empty-warning }
+pp-not-wanted = Rhybudd! Rydych wedi penderfynu peidio â defnyddio Prif Gyfrinair. { pp-empty-warning }
+
+pp-change2empty-in-fips-mode = Rydych ym modd FIPS. Mae FIPS angen Prif Gyfrinair nad yw'n wag.
+pw-change-success-title = Llwyddo i Newid eich Cyfrinair
+pw-change-failed-title = Methu Newid eich Cyfrinair
+pw-remove-button =
+    .label = Tynnu
+
+set-password =
+    .title = Newid Prif Gyfrinair
+
+primary-password-dialog =
+    .title = Prif Gyfrinair
+set-password-old-password = Cyfrinair cyfredol:
+set-password-new-password = Rhoi'r cyfrinair newydd:
+set-password-reenter-password = Rhoi'r cyfrinair eto:
+set-password-meter = Mesurydd ansawdd y cyfrinair
+set-password-meter-loading = Llwytho
+master-password-admin = Mae eich gweinyddwr yn mynnu bod gennych Brif Gyfrinair wedi'i osod er mwyn cadw cyfrineiriau.
+master-password-description = Mae Prif Gyfrinair yn cael ei ddefnyddio i amddiffyn gwybodaeth sensitif fel cyfrineiriau gwefannau.  Os fyddwch yn creu Prif Gyfrinair bydd gofyn i chi ei rhoi unwaith y sesiwn pan fydd { -brand-short-name } yn estyn gwybodaeth wedi ei gadw'n ddiogel gan y cyfrinair.
+master-password-warning = Gwnewch yn siŵr eich bod yn cofio'r Prif Gyfrinair.  Os byddwch yn anghofio eich Prif Gyfieithiad, ni fydd modd i chi gael mynediad at unrhyw wybodaeth mae'n ei amddiffyn.
+
+remove-password =
+    .title = Tynnu'r Prif Gyfrinair
+primary-password-admin = Mae eich gweinyddwr yn mynnu bod gennych Brif Gyfrinair wedi'i osod er mwyn cadw mewngofnodion a chyfrineiriau.
+primary-password-description = Mae Prif Gyfrinair yn cael ei ddefnyddio i ddiogelu gwybodaeth sensitif fel cyfrineiriau gwefannau.  Os fyddwch yn creu Prif Gyfrinair bydd gofyn i chi ei rhoi unwaith y sesiwn pan fydd { -brand-short-name } yn estyn gwybodaeth wedi ei gadw'n ddiogel gan y cyfrinair.
+primary-password-warning = Gwnewch yn siŵr eich bod yn cofio'r Prif Gyfrinair.  Os byddwch yn anghofio eich Prif Gyfieithiad, ni fydd modd i chi gael mynediad at unrhyw wybodaeth mae'n ei ddiogelu.
+
+remove-primary-password =
+    .title = Tynnu'r Prif Gyfrinair
+remove-info =
+    .value = Rhaid rhoi eich cyfrinair presennol cyn parhau:
+remove-warning1 = Mae eich Prif Gyfrinair yn cael ei ddefnyddio i ddiogelu data sensitif fel cyfrineiriau gwefannau.
+remove-warning2 = Os byddwch yn tynnu eich Prif Gyfrinair ni fydd eich gwybodaeth wedi ei ddiogelu os yw eich cyfrifiadur wedi ei gyfaddawdu.
+remove-primary-password-warning1 = Mae eich Prif Gyfrinair yn cael ei ddefnyddio i ddiogelu data sensitif fel cyfrineiriau gwefannau.
+remove-primary-password-warning2 = Os byddwch yn tynnu eich Prif Gyfrinair ni fydd eich gwybodaeth wedi ei ddiogelu os yw eich cyfrifiadur wedi ei gyfaddawdu.
+remove-password-old-password =
+    .value = Cyfrinair cyfredol:
diff --git a/l10n-cy/toolkit/toolkit/printing/printDialogs.ftl b/l10n-cy/toolkit/toolkit/printing/printDialogs.ftl
new file mode 100644
index 0000000000..0fe7753937
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/printing/printDialogs.ftl
@@ -0,0 +1,112 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+print-setup =
+    .title = Gosodiad Tudalen
+custom-prompt-title = Cyfaddasu…
+custom-prompt-prompt = Rhowch destun pennyn /troedyn cyfaddas
+basic-tab =
+    .label = Fformatio a Dewisiadau
+advanced-tab =
+    .label = Ymylon a Phennyn/Troedyn
+format-group-label =
+    .value = Fformat
+orientation-label =
+    .value = Cyfeiriadaeth:
+portrait =
+    .label = Portread
+    .accesskey = P
+landscape =
+    .label = Tirwedd
+    .accesskey = T
+scale =
+    .label = Graddfa:
+    .accesskey = r
+scale-percent =
+    .value = %
+shrink-to-fit =
+    .label = Cywasgu i Led y Dudalen
+    .accesskey = L
+options-group-label =
+    .value = Dewisiadau
+print-bg =
+    .label = Argraffu Lliwiau'r Cefndir (lliwiau a delweddau)
+    .accesskey = A
+margin-group-label-inches =
+    .value = Ymylon (modfedd)
+margin-group-label-metric =
+    .value = Ymylon (milimetr)
+margin-top =
+    .value = Brig:
+    .accesskey = B
+margin-top-invisible =
+    .value = Brig:
+margin-bottom =
+    .value = Gwaelod:
+    .accesskey = G
+margin-bottom-invisible =
+    .value = Gwaelod:
+margin-left =
+    .value = Chwith:
+    .accesskey = C
+margin-left-invisible =
+    .value = Chwith:
+margin-right =
+    .value = De:
+    .accesskey = D
+margin-right-invisible =
+    .value = De:
+header-footer-label =
+    .value = Penynnau a Throedynnau
+hf-left-label =
+    .value = Chwith:
+hf-center-label =
+    .value = Canoli:
+hf-right-label =
+    .value = De:
+header-left-tip =
+    .tooltiptext = Pennyn chwith
+header-center-tip =
+    .tooltiptext = Pennyn canol
+header-right-tip =
+    .tooltiptext = Pennyn de
+footer-left-tip =
+    .tooltiptext = Troedyn chwith
+footer-center-tip =
+    .tooltiptext = Troedyn canol
+footer-right-tip =
+    .tooltiptext = Troedyn de
+hf-blank =
+    .label = --gwag--
+hf-title =
+    .label = Teitl
+hf-url =
+    .label = URL
+hf-date-and-time =
+    .label = Dyddiad/Amser
+hf-page =
+    .label = Tudalen #
+hf-page-and-total =
+    .label = Tudalen # o #
+hf-custom =
+    .label = Cyfaddasu…
+print-preview-window =
+    .title = Rhagolwg Argraffu
+print-title =
+    .value = Teitl:
+print-preparing =
+    .value = Paratoi…
+print-progress =
+    .value = Cynnydd:
+print-window =
+    .title = Argraffu
+print-complete =
+    .value = Argraffu wedi ei Gwblhau.
+
+# Variables
+# $percent (integer) - Number of printed percentage
+print-percent =
+    .value = { $percent }%
+dialog-cancel-label = Diddymu
+dialog-close-label = Cau
diff --git a/l10n-cy/toolkit/toolkit/printing/printPreview.ftl b/l10n-cy/toolkit/toolkit/printing/printPreview.ftl
new file mode 100644
index 0000000000..21def775da
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/printing/printPreview.ftl
@@ -0,0 +1,71 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+printpreview-simplify-page-checkbox =
+    .label = Symleiddio Tudalen
+    .accesskey = S
+    .tooltiptext = Nid oes modd symleiddio'r dudalen yn awtomatig
+printpreview-simplify-page-checkbox-enabled =
+    .label = { printpreview-simplify-page-checkbox.label }
+    .accesskey = { printpreview-simplify-page-checkbox.accesskey }
+    .tooltiptext = Newid cynllun ar gyfer darllen haws
+printpreview-close =
+    .label = Cau
+    .accesskey = C
+printpreview-portrait =
+    .label = Portread
+    .accesskey = o
+printpreview-landscape =
+    .label = Tirlun
+    .accesskey = l
+printpreview-scale =
+    .value = Graddfa:
+    .accesskey = G
+printpreview-shrink-to-fit =
+    .label = Lleihau i'r Maint
+printpreview-custom =
+    .label = Cyfaddasu…
+printpreview-print =
+    .label = Argraffu…
+    .accesskey = A
+printpreview-of =
+    .value = o
+printpreview-custom-scale-prompt-title = Graddfa Cyfaddasu
+printpreview-page-setup =
+    .label = Gosodiad Tudalen…
+    .accesskey = u
+printpreview-page =
+    .value = Tudalen:
+    .accesskey = a
+# Variables
+# $sheetNum (integer) - The current sheet number
+# $sheetCount (integer) - The total number of sheets to print
+printpreview-sheet-of-sheets = { $sheetNum } o { $sheetCount }
+
+## Variables
+## $percent (integer) - menuitem percent label
+## $arrow (String) - UTF-8 arrow character for navigation buttons
+
+printpreview-percentage-value =
+    .label = { $percent }%
+printpreview-homearrow =
+    .label = { $arrow }
+    .tooltiptext = Tudalen gyntaf
+printpreview-previousarrow =
+    .label = { $arrow }
+    .tooltiptext = Tudalen blaenorol
+printpreview-nextarrow =
+    .label = { $arrow }
+    .tooltiptext = Tudalen nesaf
+printpreview-endarrow =
+    .label = { $arrow }
+    .tooltiptext = Tudalen olaf
+printpreview-homearrow-button =
+    .title = Tudalen gyntaf
+printpreview-previousarrow-button =
+    .title = Tudalen flaenorol
+printpreview-nextarrow-button =
+    .title = Tudalen nesaf
+printpreview-endarrow-button =
+    .title = Tudalen olaf
diff --git a/l10n-cy/toolkit/toolkit/printing/printUI.ftl b/l10n-cy/toolkit/toolkit/printing/printUI.ftl
new file mode 100644
index 0000000000..9bde9613ce
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/printing/printUI.ftl
@@ -0,0 +1,106 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+printui-title = Argraffu
+# Dialog title to prompt the user for a filename to save print to PDF.
+printui-save-to-pdf-title = Cadw Fel
+# Variables
+# $sheetCount (integer) - Number of paper sheets
+printui-sheets-count =
+    { $sheetCount ->
+        [zero] { $sheetCount } dalen o bapur
+        [one] { $sheetCount } dalen o bapur
+        [two] { $sheetCount } ddalen o bapur
+        [few] { $sheetCount } dalen o bapur
+        [many] { $sheetCount } dalen o bapur
+       *[other] { $sheetCount } dalen o bapur
+    }
+printui-page-range-all = Y Cyfan
+printui-page-range-custom = Cyfaddasu
+printui-page-range-label = Tudalen
+printui-page-range-picker =
+    .aria-label = Dewis yr ystod tudalen
+printui-page-custom-range-input =
+    .aria-label = Rhowch ystod tudalen cyfaddas
+    .placeholder = e.e. 2-6, 9, 12-16
+# Section title for the number of copies to print
+printui-copies-label = Copïau
+printui-orientation = Cyfeiriad
+printui-landscape = Tirlun
+printui-portrait = Portread
+# Section title for the printer or destination device to target
+printui-destination-label = Cyrchfan
+printui-destination-pdf-label = Cadw i PDF
+printui-more-settings = Rhagor o osodiadau
+printui-less-settings = Llai o osodiadau
+printui-paper-size-label = Maint papur
+# Section title (noun) for the print scaling options
+printui-scale = Graddfa
+printui-scale-fit-to-page-width = Yn ffitio i led y dudalen
+# Label for input control where user can set the scale percentage
+printui-scale-pcent = Graddfa
+# Section title (noun) for the two-sided print options
+printui-two-sided-printing = Argraffu dwy ochr
+printui-duplex-checkbox = Argraffu ar y ddwy ochr
+# Section title for miscellaneous print options
+printui-options = Dewisiadau
+printui-headers-footers-checkbox = Argraffu penynnau a throedynnau
+printui-backgrounds-checkbox = Argraffu cefndiroedd
+printui-selection-checkbox = Argraffu'r dewis yn unig
+printui-color-mode-label = Modd lliw
+printui-color-mode-color = Lliw
+printui-color-mode-bw = Du a gwyn
+printui-margins = Ymylon
+printui-margins-default = Rhagosodiad
+printui-margins-min = Lleiafswm
+printui-margins-none = Dim
+printui-margins-custom-inches = Cyfaddas (modfeddi)
+printui-margins-custom-top = Brig
+printui-margins-custom-top-inches = Brig (modfeddi)
+printui-margins-custom-bottom = Gwaelod
+printui-margins-custom-bottom-inches = Gwaelod (modfeddi)
+printui-margins-custom-left = Chwith
+printui-margins-custom-left-inches = Chwith (modfeddi)
+printui-margins-custom-right = De
+printui-margins-custom-right-inches = De (modfeddi)
+printui-system-dialog-link = Argraffu gan ddefnyddio deialog y system ...
+printui-primary-button = Argraffu
+printui-primary-button-save = Cadw
+printui-cancel-button = Diddymu
+printui-close-button = Cau
+printui-loading = Paratoi Rhagolwg
+# Reported by screen readers and other accessibility tools to indicate that
+# the print preview has focus.
+printui-preview-label =
+    .aria-label = Rhagolwg Argraffu
+printui-pages-per-sheet = Tudalennau fesul dalen
+# This is shown next to the Print button with an indefinite loading spinner
+# when the user prints a page and it is being sent to the printer.
+printui-print-progress-indicator = Argraffu…
+printui-print-progress-indicator-saving = Yn cadw…
+
+## Paper sizes that may be supported by the Save to PDF destination:
+
+printui-paper-a5 = A5
+printui-paper-a4 = A4
+printui-paper-a3 = A3
+printui-paper-a2 = A2
+printui-paper-a1 = A1
+printui-paper-a0 = A0
+printui-paper-b5 = B5
+printui-paper-b4 = B4
+printui-paper-jis-b5 = JIS-B5
+printui-paper-jis-b4 = JIS-B4
+printui-paper-letter = US Letter
+printui-paper-legal = US Legal
+printui-paper-tabloid = Tabloid
+
+## Error messages shown when a user has an invalid input
+
+printui-error-invalid-scale = Rhaid i'r raddfa fod yn rhif rhwng 10 a 200.
+printui-error-invalid-margin = Rhowch ymyl ddilys ar gyfer y maint papur a ddewiswyd.
+# Variables
+# $numPages (integer) - Number of pages
+printui-error-invalid-range = Rhaid i'r raddfa fod yn rhif rhwng 10 a { $numPages }.
+printui-error-invalid-start-overflow = Rhaid i rif y dudalen “o” fod yn llai na rhif y dudalen “i”.
diff --git a/l10n-cy/toolkit/toolkit/updates/elevation.ftl b/l10n-cy/toolkit/toolkit/updates/elevation.ftl
new file mode 100644
index 0000000000..5c8dd3ab4c
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/updates/elevation.ftl
@@ -0,0 +1,14 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+# This is temporary until bug 1521632 is fixed
+
+elevation-update-wizard =
+    .title = Diweddaru Meddalwedd
+elevation-details-link-label =
+    .value = Manylion
+elevation-error-manual = Gallwch ddiweddaru { -brand-short-name } gyda llaw drwy ymweld â'r dolenni a llwytho'r fersiwn diweddaraf:
+elevation-finished-page = Diweddariad yn Barod i'w Osod
+elevation-finished-background-page = Mae diweddariad diogelwch a sefydlogrwydd ar gyfer { -brand-short-name } wedi ei lwytho i lawr ac mae'n barod i'w osod.
+elevation-finished-background = Diweddaru:
+elevation-more-elevated = Mae'r diweddariad angen breintiau gweinyddwr. Bydd y diweddariad yn cael ei osod y tro nesaf y bydd { -brand-short-name } yn cychwyn. Mae modd ailgychwyn { -brand-short-name } nawr, parhau i weithio ac ailgychwyn yn hwyrach, neu wrthod y diweddariad.
diff --git a/l10n-cy/toolkit/toolkit/updates/history.ftl b/l10n-cy/toolkit/toolkit/updates/history.ftl
new file mode 100644
index 0000000000..75b04463eb
--- /dev/null
+++ b/l10n-cy/toolkit/toolkit/updates/history.ftl
@@ -0,0 +1,27 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+history-title = Hanes Diweddaru
+history-intro = Mae'r diweddariadau canlynol wedi eu gosod
+
+close-button-label =
+    .buttonlabelcancel = Cau
+    .title = Hanes Diweddaru
+
+no-updates-label = Dim diweddariadau wedi eu gosod eto
+name-header = Enw'r Diweddariad
+date-header = Dyddiad Gosod
+type-header = Math
+state-header = Sir/Talaith
+
+# Used to display update history
+#
+# Variables:
+#   $name (String): name of the update
+#   $buildID (String): build identifier from the local updates.xml
+update-full-build-name = { $name } ({ $buildID })
+
+update-details = Manylion
+update-installed-on = Gosodwyd ar: { $date }
+update-status = Statws: { $status }
author	Daniel Baumann <daniel.baumann@progress-linux.org>	2024-04-28 14:29:10 +0000
committer	Daniel Baumann <daniel.baumann@progress-linux.org>	2024-04-28 14:29:10 +0000
commit	2aa4a82499d4becd2284cdb482213d541b8804dd (patch)
tree	b80bf8bf13c3766139fbacc530efd0dd9d54394c /l10n-cy/toolkit
parent	Initial commit. (diff)
download	firefox-2aa4a82499d4becd2284cdb482213d541b8804dd.tar.xz firefox-2aa4a82499d4becd2284cdb482213d541b8804dd.zip