Merging upstream version 127.0.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

39 files changed, 263 insertions, 2578 deletions

diff --git a/toolkit/components/telemetry/Events.yaml b/toolkit/components/telemetry/Events.yaml
index 5d3d433a05..339fd1feb8 100644
--- a/toolkit/components/telemetry/Events.yaml
+++ b/toolkit/components/telemetry/Events.yaml
@@ -294,33 +294,6 @@ addonsManager:
     record_in_processes: ["main"]
     bug_numbers: [1433335, 1515697, 1523641, 1549770, 1590736, 1630596, 1672570, 1714251, 1749878, 1781974, 1817100, 1861295]
     release_channel_collection: opt-out
-  report:
-    description: >
-      An abuse report submitted by a user for a given extension. The object of the event
-      represent the report entry point, the value is the id of the addon being reported.
-    objects:
-      - amo
-      - menu
-      - toolbar_context_menu
-      - unified_context_menu
-      - uninstall
-    extra_keys:
-      addon_type: >
-        The type of the add-on being reported (missing on ERROR_ADDON_NOT_FOUND, ERROR_AMODETAILS_NOTFOUND
-        and ERROR_AMODETAILS_FAILURE).
-      error_type: >
-        AbuseReport Error Type (included in case of submission failures). The error types include
-        ERROR_ABORTED_SUBMIT, ERROR_ADDON_NOT_FOUND, ERROR_CLIENT, ERROR_NETWORK, ERROR_UNKNOWN,
-        ERROR_RECENT_SUBMIT, ERROR_SERVER, ERROR_AMODETAILS_NOTFOUND, ERROR_AMODETAILS_FAILURE.
-    notification_emails: ["addons-dev-internal@mozilla.com"]
-    expiry_version: "132"
-    products:
-      - "firefox"
-      - "fennec"
-      - "thunderbird"
-    record_in_processes: ["main"]
-    bug_numbers: [1544927, 1580561, 1590736, 1630596, 1672570, 1714251, 1749878, 1780746, 1781974, 1817100, 1861295]
-    release_channel_collection: opt-out
   reportSuspiciousSite:
     description: >
       Sent when a user clicks "Report Suspicious Site" on the dropdown menu of the third-
diff --git a/toolkit/components/telemetry/Histograms.json b/toolkit/components/telemetry/Histograms.json
index 4f0f0e2329..db58482aad 100644
--- a/toolkit/components/telemetry/Histograms.json
+++ b/toolkit/components/telemetry/Histograms.json
@@ -8944,7 +8944,7 @@
     "record_in_processes": ["main"],
     "products": ["firefox"],
     "alert_emails": ["fx-search-telemetry@mozilla.com"],
-    "expires_in_version": "128",
+    "expires_in_version": "131",
     "kind": "exponential",
     "low": 16,
     "high": 5000,
@@ -9738,7 +9738,7 @@
   },
   "TELEMETRY_TEST_CATEGORICAL_OPTOUT": {
     "record_in_processes": ["main", "content"],
-    "products": ["firefox", "fennec", "geckoview_streaming", "thunderbird"],
+    "products": ["firefox", "fennec", "thunderbird"],
     "alert_emails": ["telemetry-client-dev@mozilla.com"],
     "bug_numbers": [1188888],
     "expires_in_version": "never",
@@ -9956,7 +9956,7 @@
   },
   "TELEMETRY_TEST_EXPIRED": {
     "record_in_processes": ["main", "content"],
-    "products": ["firefox", "fennec", "thunderbird", "geckoview_streaming"],
+    "products": ["firefox", "fennec", "thunderbird"],
     "alert_emails": ["telemetry-client-dev@mozilla.com"],
     "expires_in_version": "4",
     "kind": "linear",
@@ -10211,32 +10211,6 @@
     "description": "a testing histogram; not meant to be touched",
     "record_into_store": ["main", "sync"]
   },
-  "TELEMETRY_TEST_STREAMING": {
-    "record_in_processes": ["main"],
-    "products": ["geckoview_streaming"],
-    "alert_emails": ["telemetry-client-dev@mozilla.com"],
-    "expires_in_version": "never",
-    "kind": "linear",
-    "low": 1,
-    "high": 2147483646,
-    "n_buckets": 10,
-    "releaseChannelCollection": "opt-out",
-    "bug_numbers": [1566366],
-    "description": "a testing histogram; not meant to be touched"
-  },
-  "TELEMETRY_TEST_STREAMING_2": {
-    "record_in_processes": ["main"],
-    "products": ["geckoview_streaming"],
-    "alert_emails": ["telemetry-client-dev@mozilla.com"],
-    "expires_in_version": "never",
-    "kind": "linear",
-    "low": 1,
-    "high": 2147483646,
-    "n_buckets": 10,
-    "releaseChannelCollection": "opt-out",
-    "bug_numbers": [1566366],
-    "description": "a testing histogram; not meant to be touched"
-  },
   "STARTUP_CRASH_DETECTED": {
     "record_in_processes": ["main", "content"],
     "products": ["firefox", "fennec", "thunderbird"],
@@ -16096,68 +16070,6 @@
     "description": "The amount of time it takes for a PageAction popup to open, keyed by addon id.",
     "keyed": true
   },
-  "WEBEXT_STORAGE_LOCAL_GET_MS": {
-    "record_in_processes": ["main", "content"],
-    "products": ["firefox", "fennec"],
-    "alert_emails": ["addons-dev-internal@mozilla.com", "lgreco@mozilla.com"],
-    "bug_numbers": [
-      1371398, 1513556, 1578225, 1623315, 1666980, 1706839, 1745271, 1777402,
-      1811155, 1861303
-    ],
-    "expires_in_version": "132",
-    "kind": "exponential",
-    "releaseChannelCollection": "opt-out",
-    "high": 50000,
-    "n_buckets": 100,
-    "description": "The amount of time it takes to perform a get via storage.local using the JSONFile backend."
-  },
-  "WEBEXT_STORAGE_LOCAL_GET_MS_BY_ADDONID": {
-    "record_in_processes": ["main", "content"],
-    "products": ["firefox", "fennec"],
-    "alert_emails": ["addons-dev-internal@mozilla.com", "lgreco@mozilla.com"],
-    "bug_numbers": [
-      1483002, 1513556, 1578225, 1623315, 1666980, 1706839, 1745271, 1777402,
-      1811155, 1861303
-    ],
-    "expires_in_version": "132",
-    "kind": "exponential",
-    "releaseChannelCollection": "opt-out",
-    "high": 50000,
-    "n_buckets": 100,
-    "description": "The amount of time it takes to perform a get via storage.local using the JSONFile backend, keyed by addon id.",
-    "keyed": true
-  },
-  "WEBEXT_STORAGE_LOCAL_SET_MS": {
-    "record_in_processes": ["main", "content"],
-    "products": ["firefox", "fennec"],
-    "alert_emails": ["addons-dev-internal@mozilla.com", "lgreco@mozilla.com"],
-    "bug_numbers": [
-      1371398, 1513556, 1578225, 1623315, 1666980, 1706839, 1745271, 1777402,
-      1811155, 1861303
-    ],
-    "expires_in_version": "132",
-    "kind": "exponential",
-    "releaseChannelCollection": "opt-out",
-    "high": 50000,
-    "n_buckets": 100,
-    "description": "The amount of time it takes to perform a set via storage.local using the JSONFile backend."
-  },
-  "WEBEXT_STORAGE_LOCAL_SET_MS_BY_ADDONID": {
-    "record_in_processes": ["main", "content"],
-    "products": ["firefox", "fennec"],
-    "alert_emails": ["addons-dev-internal@mozilla.com", "lgreco@mozilla.com"],
-    "bug_numbers": [
-      1483002, 1513556, 1578225, 1623315, 1666980, 1706839, 1745271, 1777402,
-      1811155, 1861303
-    ],
-    "expires_in_version": "132",
-    "kind": "exponential",
-    "releaseChannelCollection": "opt-out",
-    "high": 50000,
-    "n_buckets": 100,
-    "description": "The amount of time it takes to perform a set via storage.local using the JSONFile backend, keyed by addon id.",
-    "keyed": true
-  },
   "WEBEXT_STORAGE_LOCAL_IDB_GET_MS": {
     "record_in_processes": ["main", "content"],
     "products": ["firefox", "fennec"],
@@ -16863,26 +16775,6 @@
     "n_buckets": 32,
     "description": "The number of style and layout flushes that occur per Refresh Driver tick."
   },
-  "IDB_CUSTOM_OPEN_WITH_OPTIONS_COUNT": {
-    "record_in_processes": ["main", "content"],
-    "products": ["firefox", "fennec"],
-    "bug_numbers": [1566758],
-    "alert_emails": ["sgiesecke@mozilla.com"],
-    "expires_in_version": "74",
-    "kind": "categorical",
-    "labels": [
-      "system",
-      "content_file",
-      "content_http_https",
-      "content_moz_ext",
-      "content_about",
-      "content_other",
-      "expanded",
-      "other"
-    ],
-    "releaseChannelCollection": "opt-out",
-    "description": "Tracking the use of the custom IDBFactory.open overload accepting an options dictionary in one of the categories."
-  },
   "PRESSHELL_LAYOUT_TOTAL_MS_PER_TICK": {
     "record_in_processes": ["main", "content"],
     "products": ["firefox", "fennec"],
diff --git a/toolkit/components/telemetry/Scalars.yaml b/toolkit/components/telemetry/Scalars.yaml
index f63b8b5fdb..0822865b4c 100644
--- a/toolkit/components/telemetry/Scalars.yaml
+++ b/toolkit/components/telemetry/Scalars.yaml
@@ -1786,9 +1786,10 @@ extensions.startupCache:
   write_byteLength:
     bug_numbers:
       - 1767336
+      - 1892151
     description: >
       The amount of bytes writted into the Extensions StartupCache file.
-    expires: "128"
+    expires: "135"
     kind: uint
     notification_emails:
       - addons-dev-internal@mozilla.com
@@ -1800,10 +1801,11 @@ extensions.startupCache:
   read_errors:
     bug_numbers:
       - 1767336
+      - 1892151
     description: >
       The amount of times an unexpected error has been raised while
       reading the Extensions StartupCache file
-    expires: "128"
+    expires: "135"
     kind: uint
     keyed: true
     notification_emails:
@@ -2947,6 +2949,7 @@ media:
   device_hardware_decoding_support:
     bug_numbers:
       - 1850594
+      - 1892516
     description: >
       Record the hardware decoding availability on devices, the key is the name of video codec, eg. h264, av1.
     expires: never
@@ -2958,7 +2961,7 @@ media:
     products:
       - 'firefox'
     record_in_processes:
-      - 'gpu'
+      - 'main'
 
 # The following section contains content process base counters.
 dom.contentprocess:
@@ -8789,24 +8792,6 @@ contextual.services.quicksuggest:
       - 'firefox'
     record_in_processes:
       - main
-  help_dynamic_wikipedia:
-    bug_numbers:
-      - 1800993
-    description: >
-      A keyed uint recording how many times the user has clicked on the help
-      button in sponsored Firefox Suggest dynamic wikipedia results
-      in the urlbar (not including the help button). The key is the 1-based
-      index of each result.
-    expires: never
-    kind: uint
-    keyed: true
-    notification_emails:
-      - fx-search-telemetry@mozilla.com
-    release_channel_collection: opt-out
-    products:
-      - 'firefox'
-    record_in_processes:
-      - main
   help_nonsponsored:
     bug_numbers:
       - 1800993
@@ -8841,23 +8826,6 @@ contextual.services.quicksuggest:
       - 'firefox'
     record_in_processes:
       - main
-  help_weather:
-    bug_numbers:
-      - 1804536
-    description: >
-      A keyed uint recording how many times the user has clicked on the help
-      button in Firefox Suggests (a.k.a. Quick Suggest) weather results in the
-      urlbar. The key is the 1-based index of each result.
-    expires: never
-    kind: uint
-    keyed: true
-    notification_emails:
-      - fx-search-telemetry@mozilla.com
-    release_channel_collection: opt-out
-    products:
-      - 'firefox'
-    record_in_processes:
-      - main
   block_dynamic_wikipedia:
     bug_numbers:
       - 1800993
@@ -9198,7 +9166,6 @@ telemetry.test:
     products:
       - 'firefox'
       - 'fennec'
-      - 'geckoview_streaming'
       - 'thunderbird'
     record_in_processes:
       - 'main' # test_ChildScalars.js depends on this being main-only.
@@ -9216,7 +9183,6 @@ telemetry.test:
     products:
       - 'firefox'
       - 'fennec'
-      - 'geckoview_streaming'
       - 'thunderbird'
     record_in_processes:
       - 'main'
@@ -9234,7 +9200,6 @@ telemetry.test:
     products:
       - 'firefox'
       - 'fennec'
-      - 'geckoview_streaming'
       - 'thunderbird'
     record_in_processes:
       - 'main'
diff --git a/toolkit/components/telemetry/app/TelemetryControllerParent.sys.mjs b/toolkit/components/telemetry/app/TelemetryControllerParent.sys.mjs
index b9f8d5f85a..9a15142349 100644
--- a/toolkit/components/telemetry/app/TelemetryControllerParent.sys.mjs
+++ b/toolkit/components/telemetry/app/TelemetryControllerParent.sys.mjs
@@ -256,6 +256,15 @@ export var TelemetryController = Object.freeze({
   promiseInitialized() {
     return Impl.promiseInitialized();
   },
+
+  /**
+   * Allows to trigger TelemetryControllers delayed initialization now and waiting for its completion.
+   * The returned promise is guaranteed to resolve before TelemetryController is shutting down.
+   * @return {Promise} Resolved when delayed TelemetryController initialization completed.
+   */
+  ensureInitialized() {
+    return Impl.ensureInitialized();
+  },
 });
 
 var Impl = {
@@ -1158,6 +1167,18 @@ var Impl = {
     return this._delayedInitTaskDeferred.promise;
   },
 
+  /**
+   * Allows to trigger TelemetryControllers delayed initialization now and waiting for its completion.
+   * This will complete before TelemetryController is shutting down.
+   * @return {Promise} Resolved when delayed TelemetryController initialization completed.
+   */
+  ensureInitialized() {
+    if (this._delayedInitTask) {
+      return this._delayedInitTask.finalize();
+    }
+    return Promise.resolve();
+  },
+
   getCurrentPingData(aSubsession) {
     this._log.trace("getCurrentPingData - subsession: " + aSubsession);
 
diff --git a/toolkit/components/telemetry/app/TelemetryEnvironment.sys.mjs b/toolkit/components/telemetry/app/TelemetryEnvironment.sys.mjs
index 18d46a3565..5b917293c1 100644
--- a/toolkit/components/telemetry/app/TelemetryEnvironment.sys.mjs
+++ b/toolkit/components/telemetry/app/TelemetryEnvironment.sys.mjs
@@ -895,6 +895,8 @@ EnvironmentAddonBuilder.prototype = {
         hasBinaryComponents: false,
         installDay: Utils.millisecondsToDays(installDate.getTime()),
         updateDay: Utils.millisecondsToDays(updateDate.getTime()),
+        signedState: theme.signedState,
+        signedTypes: JSON.stringify(theme.signedTypes),
       };
     }
 
@@ -1672,6 +1674,7 @@ EnvironmentCache.prototype = {
     let creationDate = await profileAccessor.created;
     let resetDate = await profileAccessor.reset;
     let firstUseDate = await profileAccessor.firstUse;
+    let recoveredFromBackup = await profileAccessor.recoveredFromBackup;
 
     this._currentEnvironment.profile.creationDate =
       Utils.millisecondsToDays(creationDate);
@@ -1683,6 +1686,10 @@ EnvironmentCache.prototype = {
       this._currentEnvironment.profile.firstUseDate =
         Utils.millisecondsToDays(firstUseDate);
     }
+    if (recoveredFromBackup) {
+      this._currentEnvironment.profile.recoveredFromBackup =
+        Utils.millisecondsToDays(recoveredFromBackup);
+    }
   },
 
   /**
diff --git a/toolkit/components/telemetry/build_scripts/mozparsers/parse_events.py b/toolkit/components/telemetry/build_scripts/mozparsers/parse_events.py
index 09ed651917..1275e03a5e 100644
--- a/toolkit/components/telemetry/build_scripts/mozparsers/parse_events.py
+++ b/toolkit/components/telemetry/build_scripts/mozparsers/parse_events.py
@@ -265,12 +265,6 @@ class EventData:
                 ParserError(
                     self.identifier + ": Unknown value in products: " + product
                 ).handle_later()
-            if utils.is_geckoview_streaming_product(product):
-                ParserError(
-                    "{}: Product `{}` unsupported for Event Telemetry".format(
-                        self.identifier, product
-                    )
-                ).handle_later()
 
         # Check operating_systems.
         operating_systems = definition.get("operating_systems", [])
diff --git a/toolkit/components/telemetry/build_scripts/mozparsers/parse_histograms.py b/toolkit/components/telemetry/build_scripts/mozparsers/parse_histograms.py
index 626188bf06..92fff31a48 100644
--- a/toolkit/components/telemetry/build_scripts/mozparsers/parse_histograms.py
+++ b/toolkit/components/telemetry/build_scripts/mozparsers/parse_histograms.py
@@ -46,12 +46,6 @@ BASE_DOC_URL = (
 HISTOGRAMS_DOC_URL = BASE_DOC_URL + "collection/histograms.html"
 SCALARS_DOC_URL = BASE_DOC_URL + "collection/scalars.html"
 
-GECKOVIEW_STREAMING_SUPPORTED_KINDS = [
-    "linear",
-    "exponential",
-    "categorical",
-]
-
 
 def linear_buckets(dmin, dmax, n_buckets):
     ret_array = [0] * n_buckets
@@ -435,22 +429,6 @@ class Histogram:
                     'Histogram "%s" has unknown product "%s" in %s.\n%s'
                     % (name, product, field, DOC_URL)
                 ).handle_later()
-            if utils.is_geckoview_streaming_product(product):
-                kind = definition.get("kind")
-                if kind not in GECKOVIEW_STREAMING_SUPPORTED_KINDS:
-                    ParserError(
-                        (
-                            'Histogram "%s" is of kind "%s" which is unsupported for '
-                            'product "%s".'
-                        )
-                        % (name, kind, product)
-                    ).handle_later()
-                keyed = definition.get("keyed")
-                if keyed:
-                    ParserError(
-                        'Keyed histograms like "%s" are unsupported for product "%s"'
-                        % (name, product)
-                    ).handle_later()
 
     def check_operating_systems(self, name, definition):
         if not self._strict_type_checks:
diff --git a/toolkit/components/telemetry/build_scripts/mozparsers/parse_scalars.py b/toolkit/components/telemetry/build_scripts/mozparsers/parse_scalars.py
index 5ec591b393..b46cc7c3db 100644
--- a/toolkit/components/telemetry/build_scripts/mozparsers/parse_scalars.py
+++ b/toolkit/components/telemetry/build_scripts/mozparsers/parse_scalars.py
@@ -308,13 +308,6 @@ class ScalarType:
                     + product
                     + ".\nSee: {}".format(BASE_DOC_URL)
                 ).handle_later()
-            if utils.is_geckoview_streaming_product(product):
-                keyed = definition.get("keyed")
-                if keyed:
-                    ParserError(
-                        "%s - keyed Scalars not supported for product %s"
-                        % (self._name, product)
-                    ).handle_later()
 
         # Validate the expiration version.
         # Historical versions of Scalars.json may contain expiration versions
diff --git a/toolkit/components/telemetry/build_scripts/mozparsers/shared_telemetry_utils.py b/toolkit/components/telemetry/build_scripts/mozparsers/shared_telemetry_utils.py
index 4b4cc9f685..80ae685c45 100644
--- a/toolkit/components/telemetry/build_scripts/mozparsers/shared_telemetry_utils.py
+++ b/toolkit/components/telemetry/build_scripts/mozparsers/shared_telemetry_utils.py
@@ -26,15 +26,13 @@ KNOWN_PROCESS_FLAGS = {
     "all_childs": "AllChildren",  # Supporting files from before bug 1363725
 }
 
-GECKOVIEW_STREAMING_PRODUCT = "geckoview_streaming"
-
 SUPPORTED_PRODUCTS = {
     "firefox": "Firefox",
     "fennec": "Fennec",
-    GECKOVIEW_STREAMING_PRODUCT: "GeckoviewStreaming",
     "thunderbird": "Thunderbird",
     # Historical, deprecated values:
     # 'geckoview': 'Geckoview',
+    # "geckoview_streaming": "GeckoviewStreaming",
 }
 
 SUPPORTED_OPERATING_SYSTEMS = [
@@ -114,10 +112,6 @@ def is_valid_product(name):
     return name in SUPPORTED_PRODUCTS
 
 
-def is_geckoview_streaming_product(name):
-    return name == GECKOVIEW_STREAMING_PRODUCT
-
-
 def is_valid_os(name):
     return name in SUPPORTED_OPERATING_SYSTEMS
 
diff --git a/toolkit/components/telemetry/core/Telemetry.cpp b/toolkit/components/telemetry/core/Telemetry.cpp
index a0effb02bb..3214210c39 100644
--- a/toolkit/components/telemetry/core/Telemetry.cpp
+++ b/toolkit/components/telemetry/core/Telemetry.cpp
@@ -16,9 +16,6 @@
 #endif
 #include "base/pickle.h"
 #include "base/process_util.h"
-#if defined(MOZ_TELEMETRY_GECKOVIEW)
-#  include "geckoview/TelemetryGeckoViewPersistence.h"
-#endif
 #include "ipc/TelemetryIPCAccumulator.h"
 #include "jsapi.h"
 #include "jsfriendapi.h"
diff --git a/toolkit/components/telemetry/core/TelemetryCommon.cpp b/toolkit/components/telemetry/core/TelemetryCommon.cpp
index 7113a682c9..278763eaff 100644
--- a/toolkit/components/telemetry/core/TelemetryCommon.cpp
+++ b/toolkit/components/telemetry/core/TelemetryCommon.cpp
@@ -194,11 +194,7 @@ JSString* ToJSString(JSContext* cx, const nsAString& aStr) {
 
 SupportedProduct GetCurrentProduct() {
 #if defined(MOZ_WIDGET_ANDROID)
-  if (mozilla::StaticPrefs::toolkit_telemetry_geckoview_streaming()) {
-    return SupportedProduct::GeckoviewStreaming;
-  } else {
-    return SupportedProduct::Fennec;
-  }
+  return SupportedProduct::Fennec;
 #elif defined(MOZ_THUNDERBIRD)
   return SupportedProduct::Thunderbird;
 #else
diff --git a/toolkit/components/telemetry/core/TelemetryCommon.h b/toolkit/components/telemetry/core/TelemetryCommon.h
index 141410f150..47feef94d2 100644
--- a/toolkit/components/telemetry/core/TelemetryCommon.h
+++ b/toolkit/components/telemetry/core/TelemetryCommon.h
@@ -42,10 +42,8 @@ static_assert(static_cast<uint16_t>(RecordedProcessType::Main) == 1,
 enum class SupportedProduct : uint8_t {
   Firefox = (1 << 0),
   Fennec = (1 << 1),
-  // Note that `1 << 2` (former GeckoView) is missing in the representation
-  // but isn't necessary to be maintained, but we see no point in filling it
-  // at this time.
-  GeckoviewStreaming = (1 << 3),
+  // Note that `1 << 2` and `1 << 3` (former GeckoView, GeckoviewStreaming) are
+  // missing in the representation. We see no point in filling it at this time.
   Thunderbird = (1 << 4),
 };
 MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(SupportedProduct);
diff --git a/toolkit/components/telemetry/core/TelemetryHistogram.cpp b/toolkit/components/telemetry/core/TelemetryHistogram.cpp
index 88ac88eb9e..0ba7009d51 100644
--- a/toolkit/components/telemetry/core/TelemetryHistogram.cpp
+++ b/toolkit/components/telemetry/core/TelemetryHistogram.cpp
@@ -8,7 +8,6 @@
 
 #include <limits>
 #include "base/histogram.h"
-#include "geckoview/streaming/GeckoViewStreamingTelemetry.h"
 #include "ipc/TelemetryIPCAccumulator.h"
 #include "jsapi.h"
 #include "jsfriendapi.h"
@@ -700,15 +699,6 @@ nsresult internal_HistogramAdd(const StaticMutexAutoLock& aLock,
     return NS_OK;
   }
 
-  if (&histogram != gExpiredHistogram &&
-      GetCurrentProduct() == SupportedProduct::GeckoviewStreaming) {
-    const HistogramInfo& info = gHistogramInfos[id];
-    GeckoViewStreamingTelemetry::HistogramAccumulate(
-        nsDependentCString(info.name()),
-        info.histogramType == nsITelemetry::HISTOGRAM_CATEGORICAL, value);
-    return NS_OK;
-  }
-
   // The internal representation of a base::Histogram's buckets uses `int`.
   // Clamp large values of `value` to be INT_MAX so they continue to be treated
   // as large values (instead of negative ones).
@@ -3038,640 +3028,3 @@ size_t TelemetryHistogram::GetHistogramSizesOfIncludingThis(
 
   return n;
 }
-
-////////////////////////////////////////////////////////////////////////
-////////////////////////////////////////////////////////////////////////
-//
-// PRIVATE: GeckoView specific helpers
-
-namespace base {
-class PersistedSampleSet : public base::Histogram::SampleSet {
- public:
-  explicit PersistedSampleSet(const nsTArray<base::Histogram::Count>& aCounts,
-                              int64_t aSampleSum);
-};
-
-PersistedSampleSet::PersistedSampleSet(
-    const nsTArray<base::Histogram::Count>& aCounts, int64_t aSampleSum) {
-  // Initialize the data in the base class. See Histogram::SampleSet
-  // for the fields documentation.
-  const size_t numCounts = aCounts.Length();
-  counts_.SetLength(numCounts);
-
-  for (size_t i = 0; i < numCounts; i++) {
-    counts_[i] = aCounts[i];
-    redundant_count_ += aCounts[i];
-  }
-  sum_ = aSampleSum;
-};
-}  // namespace base
-
-namespace {
-/**
- * Helper function to write histogram properties to JSON.
- * Please note that this needs to be called between
- * StartObjectProperty/EndObject calls that mark the histogram's
- * JSON creation.
- */
-void internal_ReflectHistogramToJSON(const HistogramSnapshotData& aSnapshot,
-                                     mozilla::JSONWriter& aWriter) {
-  aWriter.IntProperty("sum", aSnapshot.mSampleSum);
-
-  // Fill the "counts" property.
-  aWriter.StartArrayProperty("counts");
-  for (size_t i = 0; i < aSnapshot.mBucketCounts.Length(); i++) {
-    aWriter.IntElement(aSnapshot.mBucketCounts[i]);
-  }
-  aWriter.EndArray();
-}
-
-bool internal_CanRecordHistogram(const HistogramID id, ProcessID aProcessType) {
-  // Check if we are allowed to record the data.
-  if (!CanRecordDataset(gHistogramInfos[id].dataset, internal_CanRecordBase(),
-                        internal_CanRecordExtended())) {
-    return false;
-  }
-
-  // Check if we're allowed to record in the given process.
-  if (aProcessType == ProcessID::Parent && !internal_IsRecordingEnabled(id)) {
-    return false;
-  }
-
-  if (aProcessType != ProcessID::Parent &&
-      !CanRecordInProcess(gHistogramInfos[id].record_in_processes,
-                          aProcessType)) {
-    return false;
-  }
-
-  // Don't record if the current platform is not enabled
-  if (!CanRecordProduct(gHistogramInfos[id].products)) {
-    return false;
-  }
-
-  return true;
-}
-
-nsresult internal_ParseHistogramData(
-    JSContext* aCx, JS::Handle<JS::PropertyKey> aEntryId,
-    JS::Handle<JSObject*> aContainerObj, nsACString& aOutName,
-    nsTArray<base::Histogram::Count>& aOutCountArray, int64_t& aOutSum) {
-  // Get the histogram name.
-  nsAutoJSString histogramName;
-  if (!histogramName.init(aCx, aEntryId)) {
-    JS_ClearPendingException(aCx);
-    return NS_ERROR_FAILURE;
-  }
-
-  CopyUTF16toUTF8(histogramName, aOutName);
-
-  // Get the data for this histogram.
-  JS::Rooted<JS::Value> histogramData(aCx);
-  if (!JS_GetPropertyById(aCx, aContainerObj, aEntryId, &histogramData)) {
-    JS_ClearPendingException(aCx);
-    return NS_ERROR_FAILURE;
-  }
-
-  if (!histogramData.isObject()) {
-    // base::Histogram data need to be an object. If that's not the case, skip
-    // it and try to load the rest of the data.
-    return NS_ERROR_FAILURE;
-  }
-
-  // Get the "sum" property.
-  JS::Rooted<JS::Value> sumValue(aCx);
-  JS::Rooted<JSObject*> histogramObj(aCx, &histogramData.toObject());
-  if (!JS_GetProperty(aCx, histogramObj, "sum", &sumValue)) {
-    JS_ClearPendingException(aCx);
-    return NS_ERROR_FAILURE;
-  }
-
-  if (!JS::ToInt64(aCx, sumValue, &aOutSum)) {
-    JS_ClearPendingException(aCx);
-    return NS_ERROR_FAILURE;
-  }
-
-  // Get the "counts" array.
-  JS::Rooted<JS::Value> countsArray(aCx);
-  bool countsIsArray = false;
-  if (!JS_GetProperty(aCx, histogramObj, "counts", &countsArray) ||
-      !JS::IsArrayObject(aCx, countsArray, &countsIsArray)) {
-    JS_ClearPendingException(aCx);
-    return NS_ERROR_FAILURE;
-  }
-
-  if (!countsIsArray) {
-    // The "counts" property needs to be an array. If this is not the case,
-    // skip this histogram.
-    return NS_ERROR_FAILURE;
-  }
-
-  // Get the length of the array.
-  uint32_t countsLen = 0;
-  JS::Rooted<JSObject*> countsArrayObj(aCx, &countsArray.toObject());
-  if (!JS::GetArrayLength(aCx, countsArrayObj, &countsLen)) {
-    JS_ClearPendingException(aCx);
-    return NS_ERROR_FAILURE;
-  }
-
-  // Parse the "counts" in the array.
-  for (uint32_t arrayIdx = 0; arrayIdx < countsLen; arrayIdx++) {
-    JS::Rooted<JS::Value> elementValue(aCx);
-    int countAsInt = 0;
-    if (!JS_GetElement(aCx, countsArrayObj, arrayIdx, &elementValue) ||
-        !JS::ToInt32(aCx, elementValue, &countAsInt)) {
-      JS_ClearPendingException(aCx);
-      return NS_ERROR_FAILURE;
-    }
-    aOutCountArray.AppendElement(countAsInt);
-  }
-
-  return NS_OK;
-}
-
-}  // Anonymous namespace
-
-////////////////////////////////////////////////////////////////////////
-////////////////////////////////////////////////////////////////////////
-//
-// PUBLIC: GeckoView serialization/deserialization functions.
-
-nsresult TelemetryHistogram::SerializeHistograms(mozilla::JSONWriter& aWriter) {
-  MOZ_ASSERT(XRE_IsParentProcess(),
-             "Only save histograms in the parent process");
-  if (!XRE_IsParentProcess()) {
-    return NS_ERROR_FAILURE;
-  }
-
-  // Include the GPU process in histogram snapshots only if we actually tried
-  // to launch a process for it.
-  bool includeGPUProcess = internal_AttemptedGPUProcess();
-
-  // Take a snapshot of the histograms.
-  HistogramProcessSnapshotsArray processHistArray;
-  {
-    StaticMutexAutoLock locker(gTelemetryHistogramMutex);
-    // We always request the "opt-in"/"prerelease" dataset: we internally
-    // record the right subset, so this will only return "prerelease" if
-    // it was recorded.
-    if (NS_FAILED(internal_GetHistogramsSnapshot(
-            locker, "main"_ns, nsITelemetry::DATASET_PRERELEASE_CHANNELS,
-            false /* aClearSubsession */, includeGPUProcess,
-            false /* aFilterTest */, processHistArray))) {
-      return NS_ERROR_FAILURE;
-    }
-  }
-
-  // Make the JSON calls on the stashed histograms for every process
-  for (uint32_t process = 0; process < processHistArray.length(); ++process) {
-    aWriter.StartObjectProperty(
-        mozilla::MakeStringSpan(GetNameForProcessID(ProcessID(process))));
-
-    for (const HistogramSnapshotInfo& hData : processHistArray[process]) {
-      HistogramID id = hData.histogramID;
-
-      aWriter.StartObjectProperty(
-          mozilla::MakeStringSpan(gHistogramInfos[id].name()));
-      internal_ReflectHistogramToJSON(hData.data, aWriter);
-      aWriter.EndObject();
-    }
-    aWriter.EndObject();
-  }
-
-  return NS_OK;
-}
-
-nsresult TelemetryHistogram::SerializeKeyedHistograms(
-    mozilla::JSONWriter& aWriter) {
-  MOZ_ASSERT(XRE_IsParentProcess(),
-             "Only save keyed histograms in the parent process");
-  if (!XRE_IsParentProcess()) {
-    return NS_ERROR_FAILURE;
-  }
-
-  // Include the GPU process in histogram snapshots only if we actually tried
-  // to launch a process for it.
-  bool includeGPUProcess = internal_AttemptedGPUProcess();
-
-  // Take a snapshot of the keyed histograms.
-  KeyedHistogramProcessSnapshotsArray processHistArray;
-  {
-    StaticMutexAutoLock locker(gTelemetryHistogramMutex);
-    // We always request the "opt-in"/"prerelease" dataset: we internally
-    // record the right subset, so this will only return "prerelease" if
-    // it was recorded.
-    if (NS_FAILED(internal_GetKeyedHistogramsSnapshot(
-            locker, "main"_ns, nsITelemetry::DATASET_PRERELEASE_CHANNELS,
-            false /* aClearSubsession */, includeGPUProcess,
-            false /* aFilterTest */, processHistArray))) {
-      return NS_ERROR_FAILURE;
-    }
-  }
-
-  // Serialize the keyed histograms for every process.
-  for (uint32_t process = 0; process < processHistArray.length(); ++process) {
-    aWriter.StartObjectProperty(
-        mozilla::MakeStringSpan(GetNameForProcessID(ProcessID(process))));
-
-    const KeyedHistogramSnapshotsArray& hArray = processHistArray[process];
-    for (size_t i = 0; i < hArray.length(); ++i) {
-      const KeyedHistogramSnapshotInfo& hData = hArray[i];
-      HistogramID id = hData.histogramId;
-      const HistogramInfo& info = gHistogramInfos[id];
-
-      aWriter.StartObjectProperty(mozilla::MakeStringSpan(info.name()));
-
-      // Each key is a new object with a "sum" and a "counts" property.
-      for (const auto& entry : hData.data) {
-        const HistogramSnapshotData& keyData = entry.GetData();
-        aWriter.StartObjectProperty(PromiseFlatCString(entry.GetKey()));
-        internal_ReflectHistogramToJSON(keyData, aWriter);
-        aWriter.EndObject();
-      }
-
-      aWriter.EndObject();
-    }
-    aWriter.EndObject();
-  }
-
-  return NS_OK;
-}
-
-nsresult TelemetryHistogram::DeserializeHistograms(
-    JSContext* aCx, JS::Handle<JS::Value> aData) {
-  MOZ_ASSERT(XRE_IsParentProcess(),
-             "Only load histograms in the parent process");
-  if (!XRE_IsParentProcess()) {
-    return NS_ERROR_FAILURE;
-  }
-
-  // Telemetry is disabled. This should never happen, but let's leave this check
-  // for consistency with other histogram updates routines.
-  if (!internal_CanRecordBase()) {
-    return NS_OK;
-  }
-
-  typedef std::tuple<nsCString, nsTArray<base::Histogram::Count>, int64_t>
-      PersistedHistogramTuple;
-  typedef mozilla::Vector<PersistedHistogramTuple> PersistedHistogramArray;
-  typedef mozilla::Vector<PersistedHistogramArray> PersistedHistogramStorage;
-
-  // Before updating the histograms, we need to get the data out of the JS
-  // wrappers. We can't hold the histogram mutex while handling JS stuff.
-  // Build a <histogram name, value> map.
-  JS::Rooted<JSObject*> histogramDataObj(aCx, &aData.toObject());
-  JS::Rooted<JS::IdVector> processes(aCx, JS::IdVector(aCx));
-  if (!JS_Enumerate(aCx, histogramDataObj, &processes)) {
-    // We can't even enumerate the processes in the loaded data, so
-    // there is nothing we could recover from the persistence file. Bail out.
-    JS_ClearPendingException(aCx);
-    return NS_ERROR_FAILURE;
-  }
-
-  // Make sure we have enough storage for all the processes.
-  PersistedHistogramStorage histogramsToUpdate;
-  if (!histogramsToUpdate.resize(static_cast<uint32_t>(ProcessID::Count))) {
-    return NS_ERROR_OUT_OF_MEMORY;
-  }
-
-  // The following block of code attempts to extract as much data as possible
-  // from the serialized JSON, even in case of light data corruptions: if, for
-  // example, the data for a single process is corrupted or is in an unexpected
-  // form, we press on and attempt to load the data for the other processes.
-  JS::Rooted<JS::PropertyKey> process(aCx);
-  for (auto& processVal : processes) {
-    // This is required as JS API calls require an Handle<jsid> and not a
-    // plain jsid.
-    process = processVal;
-    // Get the process name.
-    nsAutoJSString processNameJS;
-    if (!processNameJS.init(aCx, process)) {
-      JS_ClearPendingException(aCx);
-      continue;
-    }
-
-    // Make sure it's valid. Note that this is safe to call outside
-    // of a locked section.
-    NS_ConvertUTF16toUTF8 processName(processNameJS);
-    ProcessID processID = GetIDForProcessName(processName.get());
-    if (processID == ProcessID::Count) {
-      NS_WARNING(
-          nsPrintfCString("Failed to get process ID for %s", processName.get())
-              .get());
-      continue;
-    }
-
-    // And its probes.
-    JS::Rooted<JS::Value> processData(aCx);
-    if (!JS_GetPropertyById(aCx, histogramDataObj, process, &processData)) {
-      JS_ClearPendingException(aCx);
-      continue;
-    }
-
-    if (!processData.isObject()) {
-      // |processData| should be an object containing histograms. If this is
-      // not the case, silently skip and try to load the data for the other
-      // processes.
-      continue;
-    }
-
-    // Iterate through each histogram.
-    JS::Rooted<JSObject*> processDataObj(aCx, &processData.toObject());
-    JS::Rooted<JS::IdVector> histograms(aCx, JS::IdVector(aCx));
-    if (!JS_Enumerate(aCx, processDataObj, &histograms)) {
-      JS_ClearPendingException(aCx);
-      continue;
-    }
-
-    // Get a reference to the deserialized data for this process.
-    PersistedHistogramArray& deserializedProcessData =
-        histogramsToUpdate[static_cast<uint32_t>(processID)];
-
-    JS::Rooted<JS::PropertyKey> histogram(aCx);
-    for (auto& histogramVal : histograms) {
-      histogram = histogramVal;
-
-      int64_t sum = 0;
-      nsTArray<base::Histogram::Count> deserializedCounts;
-      nsCString histogramName;
-      if (NS_FAILED(internal_ParseHistogramData(aCx, histogram, processDataObj,
-                                                histogramName,
-                                                deserializedCounts, sum))) {
-        continue;
-      }
-
-      // Finally append the deserialized data to the storage.
-      if (!deserializedProcessData.emplaceBack(std::make_tuple(
-              std::move(histogramName), std::move(deserializedCounts), sum))) {
-        return NS_ERROR_OUT_OF_MEMORY;
-      }
-    }
-  }
-
-  // Update the histogram storage.
-  {
-    StaticMutexAutoLock locker(gTelemetryHistogramMutex);
-
-    for (uint32_t process = 0; process < histogramsToUpdate.length();
-         ++process) {
-      PersistedHistogramArray& processArray = histogramsToUpdate[process];
-
-      for (auto& histogramData : processArray) {
-        // Attempt to get the corresponding ID for the deserialized histogram
-        // name.
-        HistogramID id;
-        if (NS_FAILED(internal_GetHistogramIdByName(
-                locker, std::get<0>(histogramData), &id))) {
-          continue;
-        }
-
-        ProcessID procID = static_cast<ProcessID>(process);
-        if (!internal_CanRecordHistogram(id, procID)) {
-          // We're not allowed to record this, so don't try to restore it.
-          continue;
-        }
-
-        // Get the Histogram instance: this will instantiate it if it doesn't
-        // exist.
-        Histogram* w = internal_GetHistogramById(locker, id, procID);
-        MOZ_ASSERT(w);
-
-        if (!w || w->IsExpired()) {
-          continue;
-        }
-
-        base::Histogram* h = nullptr;
-        constexpr auto store = "main"_ns;
-        if (!w->GetHistogram(store, &h)) {
-          continue;
-        }
-        MOZ_ASSERT(h);
-
-        if (!h) {
-          // Don't restore expired histograms.
-          continue;
-        }
-
-        // Make sure that histogram counts have matching sizes. If not,
-        // |AddSampleSet| will fail and crash.
-        size_t numCounts = std::get<1>(histogramData).Length();
-        if (h->bucket_count() != numCounts) {
-          MOZ_ASSERT(false,
-                     "The number of restored buckets does not match with the "
-                     "on in the definition");
-          continue;
-        }
-
-        // Update the data for the histogram.
-        h->AddSampleSet(base::PersistedSampleSet(
-            std::move(std::get<1>(histogramData)), std::get<2>(histogramData)));
-      }
-    }
-  }
-
-  return NS_OK;
-}
-
-nsresult TelemetryHistogram::DeserializeKeyedHistograms(
-    JSContext* aCx, JS::Handle<JS::Value> aData) {
-  MOZ_ASSERT(XRE_IsParentProcess(),
-             "Only load keyed histograms in the parent process");
-  if (!XRE_IsParentProcess()) {
-    return NS_ERROR_FAILURE;
-  }
-
-  // Telemetry is disabled. This should never happen, but let's leave this check
-  // for consistency with other histogram updates routines.
-  if (!internal_CanRecordBase()) {
-    return NS_OK;
-  }
-
-  typedef std::tuple<nsCString, nsCString, nsTArray<base::Histogram::Count>,
-                     int64_t>
-      PersistedKeyedHistogramTuple;
-  typedef mozilla::Vector<PersistedKeyedHistogramTuple>
-      PersistedKeyedHistogramArray;
-  typedef mozilla::Vector<PersistedKeyedHistogramArray>
-      PersistedKeyedHistogramStorage;
-
-  // Before updating the histograms, we need to get the data out of the JS
-  // wrappers. We can't hold the histogram mutex while handling JS stuff.
-  // Build a <histogram name, value> map.
-  JS::Rooted<JSObject*> histogramDataObj(aCx, &aData.toObject());
-  JS::Rooted<JS::IdVector> processes(aCx, JS::IdVector(aCx));
-  if (!JS_Enumerate(aCx, histogramDataObj, &processes)) {
-    // We can't even enumerate the processes in the loaded data, so
-    // there is nothing we could recover from the persistence file. Bail out.
-    JS_ClearPendingException(aCx);
-    return NS_ERROR_FAILURE;
-  }
-
-  // Make sure we have enough storage for all the processes.
-  PersistedKeyedHistogramStorage histogramsToUpdate;
-  if (!histogramsToUpdate.resize(static_cast<uint32_t>(ProcessID::Count))) {
-    return NS_ERROR_OUT_OF_MEMORY;
-  }
-
-  // The following block of code attempts to extract as much data as possible
-  // from the serialized JSON, even in case of light data corruptions: if, for
-  // example, the data for a single process is corrupted or is in an unexpected
-  // form, we press on and attempt to load the data for the other processes.
-  JS::Rooted<JS::PropertyKey> process(aCx);
-  for (auto& processVal : processes) {
-    // This is required as JS API calls require an Handle<jsid> and not a
-    // plain jsid.
-    process = processVal;
-    // Get the process name.
-    nsAutoJSString processNameJS;
-    if (!processNameJS.init(aCx, process)) {
-      JS_ClearPendingException(aCx);
-      continue;
-    }
-
-    // Make sure it's valid. Note that this is safe to call outside
-    // of a locked section.
-    NS_ConvertUTF16toUTF8 processName(processNameJS);
-    ProcessID processID = GetIDForProcessName(processName.get());
-    if (processID == ProcessID::Count) {
-      NS_WARNING(
-          nsPrintfCString("Failed to get process ID for %s", processName.get())
-              .get());
-      continue;
-    }
-
-    // And its probes.
-    JS::Rooted<JS::Value> processData(aCx);
-    if (!JS_GetPropertyById(aCx, histogramDataObj, process, &processData)) {
-      JS_ClearPendingException(aCx);
-      continue;
-    }
-
-    if (!processData.isObject()) {
-      // |processData| should be an object containing histograms. If this is
-      // not the case, silently skip and try to load the data for the other
-      // processes.
-      continue;
-    }
-
-    // Iterate through each keyed histogram.
-    JS::Rooted<JSObject*> processDataObj(aCx, &processData.toObject());
-    JS::Rooted<JS::IdVector> histograms(aCx, JS::IdVector(aCx));
-    if (!JS_Enumerate(aCx, processDataObj, &histograms)) {
-      JS_ClearPendingException(aCx);
-      continue;
-    }
-
-    // Get a reference to the deserialized data for this process.
-    PersistedKeyedHistogramArray& deserializedProcessData =
-        histogramsToUpdate[static_cast<uint32_t>(processID)];
-
-    JS::Rooted<JS::PropertyKey> histogram(aCx);
-    for (auto& histogramVal : histograms) {
-      histogram = histogramVal;
-      // Get the histogram name.
-      nsAutoJSString histogramName;
-      if (!histogramName.init(aCx, histogram)) {
-        JS_ClearPendingException(aCx);
-        continue;
-      }
-
-      // Get the data for this histogram.
-      JS::Rooted<JS::Value> histogramData(aCx);
-      if (!JS_GetPropertyById(aCx, processDataObj, histogram, &histogramData)) {
-        JS_ClearPendingException(aCx);
-        continue;
-      }
-
-      // Iterate through each key in the histogram.
-      JS::Rooted<JSObject*> keysDataObj(aCx, &histogramData.toObject());
-      JS::Rooted<JS::IdVector> keys(aCx, JS::IdVector(aCx));
-      if (!JS_Enumerate(aCx, keysDataObj, &keys)) {
-        JS_ClearPendingException(aCx);
-        continue;
-      }
-
-      JS::Rooted<JS::PropertyKey> key(aCx);
-      for (auto& keyVal : keys) {
-        key = keyVal;
-
-        int64_t sum = 0;
-        nsTArray<base::Histogram::Count> deserializedCounts;
-        nsCString keyName;
-        if (NS_FAILED(internal_ParseHistogramData(
-                aCx, key, keysDataObj, keyName, deserializedCounts, sum))) {
-          continue;
-        }
-
-        // Finally append the deserialized data to the storage.
-        if (!deserializedProcessData.emplaceBack(std::make_tuple(
-                nsCString(NS_ConvertUTF16toUTF8(histogramName)),
-                std::move(keyName), std::move(deserializedCounts), sum))) {
-          return NS_ERROR_OUT_OF_MEMORY;
-        }
-      }
-    }
-  }
-
-  // Update the keyed histogram storage.
-  {
-    StaticMutexAutoLock locker(gTelemetryHistogramMutex);
-
-    for (uint32_t process = 0; process < histogramsToUpdate.length();
-         ++process) {
-      PersistedKeyedHistogramArray& processArray = histogramsToUpdate[process];
-
-      for (auto& histogramData : processArray) {
-        // Attempt to get the corresponding ID for the deserialized histogram
-        // name.
-        HistogramID id;
-        if (NS_FAILED(internal_GetHistogramIdByName(
-                locker, std::get<0>(histogramData), &id))) {
-          continue;
-        }
-
-        ProcessID procID = static_cast<ProcessID>(process);
-        if (!internal_CanRecordHistogram(id, procID)) {
-          // We're not allowed to record this, so don't try to restore it.
-          continue;
-        }
-
-        KeyedHistogram* keyed = internal_GetKeyedHistogramById(id, procID);
-        MOZ_ASSERT(keyed);
-
-        if (!keyed || keyed->IsExpired()) {
-          // Don't restore if we don't have a destination storage or the
-          // histogram is expired.
-          continue;
-        }
-
-        // Get data for the key we're looking for.
-        base::Histogram* h = nullptr;
-        if (NS_FAILED(keyed->GetHistogram("main"_ns, std::get<1>(histogramData),
-                                          &h))) {
-          continue;
-        }
-        MOZ_ASSERT(h);
-
-        if (!h) {
-          // Don't restore if we don't have a destination storage.
-          continue;
-        }
-
-        // Make sure that histogram counts have matching sizes. If not,
-        // |AddSampleSet| will fail and crash.
-        size_t numCounts = std::get<2>(histogramData).Length();
-        if (h->bucket_count() != numCounts) {
-          MOZ_ASSERT(false,
-                     "The number of restored buckets does not match with the "
-                     "on in the definition");
-          continue;
-        }
-
-        // Update the data for the histogram.
-        h->AddSampleSet(base::PersistedSampleSet(
-            std::move(std::get<2>(histogramData)), std::get<3>(histogramData)));
-      }
-    }
-  }
-
-  return NS_OK;
-}
diff --git a/toolkit/components/telemetry/core/TelemetryHistogram.h b/toolkit/components/telemetry/core/TelemetryHistogram.h
index 9f415f3637..f5aaa60634 100644
--- a/toolkit/components/telemetry/core/TelemetryHistogram.h
+++ b/toolkit/components/telemetry/core/TelemetryHistogram.h
@@ -12,11 +12,6 @@
 #include "nsXULAppAPI.h"
 #include "TelemetryCommon.h"
 
-namespace mozilla {
-// This is only used for the GeckoView persistence.
-class JSONWriter;
-}  // namespace mozilla
-
 // This module is internal to Telemetry.  It encapsulates Telemetry's
 // histogram accumulation and storage logic.  It should only be used by
 // Telemetry.cpp.  These functions should not be used anywhere else.
@@ -110,15 +105,6 @@ nsresult GetKeyedHistogramSnapshots(JSContext* aCx,
 
 size_t GetHistogramSizesOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf);
 
-// These functions are only meant to be used for GeckoView persistence.
-// They are responsible for updating in-memory probes with the data persisted
-// on the disk and vice-versa.
-nsresult SerializeHistograms(mozilla::JSONWriter& aWriter);
-nsresult SerializeKeyedHistograms(mozilla::JSONWriter& aWriter);
-nsresult DeserializeHistograms(JSContext* aCx, JS::Handle<JS::Value> aData);
-nsresult DeserializeKeyedHistograms(JSContext* aCx,
-                                    JS::Handle<JS::Value> aData);
-
 }  // namespace TelemetryHistogram
 
 #endif  // TelemetryHistogram_h__
diff --git a/toolkit/components/telemetry/core/TelemetryScalar.cpp b/toolkit/components/telemetry/core/TelemetryScalar.cpp
index 8a121e8f3f..312e25ddc4 100644
--- a/toolkit/components/telemetry/core/TelemetryScalar.cpp
+++ b/toolkit/components/telemetry/core/TelemetryScalar.cpp
@@ -6,7 +6,6 @@
 
 #include "TelemetryScalar.h"
 
-#include "geckoview/streaming/GeckoViewStreamingTelemetry.h"
 #include "ipc/TelemetryIPCAccumulator.h"
 #include "js/Array.h"               // JS::GetArrayLength, JS::IsArrayObject
 #include "js/PropertyAndElement.h"  // JS_DefineProperty, JS_DefineUCProperty, JS_Enumerate, JS_GetElement, JS_GetProperty, JS_GetPropertyById, JS_HasProperty
@@ -27,6 +26,7 @@
 #include "nsJSUtils.h"
 #include "nsPrintfCString.h"
 #include "nsVariant.h"
+#include "TelemetryCommon.h"
 #include "TelemetryScalarData.h"
 
 using mozilla::MakeUnique;
@@ -112,11 +112,6 @@ const uint32_t kMaximumScalarNameLength = 40;
 const uint32_t kScalarCount =
     static_cast<uint32_t>(mozilla::Telemetry::ScalarID::ScalarCount);
 
-// To stop growing unbounded in memory while waiting for scalar deserialization
-// to finish, we immediately apply pending operations if the array reaches
-// a certain high water mark of elements.
-const size_t kScalarActionsArrayHighWaterMark = 10000;
-
 const char* TEST_SCALAR_PREFIX = "telemetry.test.";
 
 // The max offset supported by gScalarStoresTable for static scalars' stores.
@@ -284,45 +279,6 @@ ScalarResult GetVariantFromIVariant(nsIVariant* aInput, uint32_t aScalarKind,
   return ScalarResult::Ok;
 }
 
-/**
- * Write a nsIVariant with a JSONWriter, used for GeckoView persistence.
- */
-nsresult WriteVariantToJSONWriter(
-    uint32_t aScalarType, nsIVariant* aInputValue,
-    const mozilla::Span<const char>& aPropertyName,
-    mozilla::JSONWriter& aWriter) {
-  MOZ_ASSERT(aInputValue);
-
-  switch (aScalarType) {
-    case nsITelemetry::SCALAR_TYPE_COUNT: {
-      uint32_t val = 0;
-      nsresult rv = aInputValue->GetAsUint32(&val);
-      NS_ENSURE_SUCCESS(rv, rv);
-      aWriter.IntProperty(aPropertyName, val);
-      break;
-    }
-    case nsITelemetry::SCALAR_TYPE_STRING: {
-      nsCString val;
-      nsresult rv = aInputValue->GetAsACString(val);
-      NS_ENSURE_SUCCESS(rv, rv);
-      aWriter.StringProperty(aPropertyName, val);
-      break;
-    }
-    case nsITelemetry::SCALAR_TYPE_BOOLEAN: {
-      bool val = false;
-      nsresult rv = aInputValue->GetAsBool(&val);
-      NS_ENSURE_SUCCESS(rv, rv);
-      aWriter.BoolProperty(aPropertyName, val);
-      break;
-    }
-    default:
-      MOZ_ASSERT(false, "Unknown scalar kind.");
-      return NS_ERROR_FAILURE;
-  }
-
-  return NS_OK;
-}
-
 // Implements the methods for ScalarInfo.
 const char* ScalarInfo::name() const {
   return &gScalarsStringTable[this->name_offset];
@@ -517,10 +473,6 @@ ScalarResult ScalarUnsigned::SetValue(nsIVariant* aValue) {
 }
 
 void ScalarUnsigned::SetValue(uint32_t aValue) {
-  if (GetCurrentProduct() == SupportedProduct::GeckoviewStreaming) {
-    GeckoViewStreamingTelemetry::UintScalarSet(mName, aValue);
-    return;
-  }
   for (auto& val : mStorage) {
     val = aValue;
   }
@@ -544,7 +496,6 @@ ScalarResult ScalarUnsigned::AddValue(nsIVariant* aValue) {
 }
 
 void ScalarUnsigned::AddValue(uint32_t aValue) {
-  MOZ_ASSERT(GetCurrentProduct() != SupportedProduct::GeckoviewStreaming);
   for (auto& val : mStorage) {
     val += aValue;
   }
@@ -552,7 +503,6 @@ void ScalarUnsigned::AddValue(uint32_t aValue) {
 }
 
 ScalarResult ScalarUnsigned::SetMaximum(nsIVariant* aValue) {
-  MOZ_ASSERT(GetCurrentProduct() != SupportedProduct::GeckoviewStreaming);
   ScalarResult sr = CheckInput(aValue);
   if (sr == ScalarResult::UnsignedNegativeValue) {
     return sr;
@@ -678,13 +628,6 @@ ScalarResult ScalarString::SetValue(nsIVariant* aValue) {
 
 ScalarResult ScalarString::SetValue(const nsAString& aValue) {
   auto str = Substring(aValue, 0, kMaximumStringValueLength);
-  if (GetCurrentProduct() == SupportedProduct::GeckoviewStreaming) {
-    GeckoViewStreamingTelemetry::StringScalarSet(mName,
-                                                 NS_ConvertUTF16toUTF8(str));
-    return aValue.Length() > kMaximumStringValueLength
-               ? ScalarResult::StringTooLong
-               : ScalarResult::Ok;
-  }
   for (auto& val : mStorage) {
     val.Assign(str);
   }
@@ -779,10 +722,6 @@ ScalarResult ScalarBoolean::SetValue(nsIVariant* aValue) {
 };
 
 void ScalarBoolean::SetValue(bool aValue) {
-  if (GetCurrentProduct() == SupportedProduct::GeckoviewStreaming) {
-    GeckoViewStreamingTelemetry::BoolScalarSet(mName, aValue);
-    return;
-  }
   for (auto& val : mStorage) {
     val = aValue;
   }
@@ -1208,20 +1147,6 @@ ProcessesKeyedScalarsMapType gKeyedScalarStorageMap;
 // needed to support "build faster" in local developer builds.
 ProcessesScalarsMapType gDynamicBuiltinScalarStorageMap;
 ProcessesKeyedScalarsMapType gDynamicBuiltinKeyedScalarStorageMap;
-
-// Whether or not the deserialization of persisted scalars is still in progress.
-// This is never the case on Desktop or Fennec.
-// Only GeckoView restores persisted scalars.
-bool gIsDeserializing = false;
-// This batches scalar accumulations that should be applied once loading
-// finished.
-StaticAutoPtr<nsTArray<ScalarAction>> gScalarsActions;
-StaticAutoPtr<nsTArray<KeyedScalarAction>> gKeyedScalarsActions;
-
-bool internal_IsScalarDeserializing(const StaticMutexAutoLock& lock) {
-  return gIsDeserializing;
-}
-
 }  // namespace
 
 ////////////////////////////////////////////////////////////////////////
@@ -1402,8 +1327,6 @@ bool internal_CanRecordForScalarID(const StaticMutexAutoLock& lock,
  * @param aKeyed Are we attempting to write a keyed scalar?
  * @param aForce Whether to allow recording even if the probe is not allowed on
  *        the current process.
- *        This must only be true for GeckoView persistence and recorded
- *        actions.
  * @return ScalarResult::Ok if we can record, an error code otherwise.
  */
 ScalarResult internal_CanRecordScalar(const StaticMutexAutoLock& lock,
@@ -1546,108 +1469,6 @@ nsresult internal_GetScalarByEnum(const StaticMutexAutoLock& lock,
   return NS_OK;
 }
 
-void internal_ApplyPendingOperations(const StaticMutexAutoLock& lock);
-
-/**
- * Record the given action on a scalar into the pending actions list.
- *
- * If the pending actions list overflows the high water mark length
- * all operations are immediately applied, including the passed action.
- *
- * @param aScalarAction The action to record.
- */
-void internal_RecordScalarAction(const StaticMutexAutoLock& lock,
-                                 const ScalarAction& aScalarAction) {
-  // Make sure to have the storage.
-  if (!gScalarsActions) {
-    gScalarsActions = new nsTArray<ScalarAction>();
-  }
-
-  // Store the action.
-  gScalarsActions->AppendElement(aScalarAction);
-
-  // If this action overflows the pending actions array, we immediately apply
-  // pending operations and assume loading is over. If loading still happens
-  // afterwards, some scalar values might be overwritten and inconsistent, but
-  // we won't lose operations on otherwise untouched probes.
-  if (gScalarsActions->Length() > kScalarActionsArrayHighWaterMark) {
-    internal_ApplyPendingOperations(lock);
-    return;
-  }
-}
-
-/**
- * Record the given action on a scalar on the main process into the pending
- * actions list.
- *
- * If the pending actions list overflows the high water mark length
- * all operations are immediately applied, including the passed action.
- *
- * @param aId The scalar's ID this action applies to
- * @param aDynamic Determines if the scalar is dynamic
- * @param aAction The action to record
- * @param aValue The additional data for the recorded action
- */
-void internal_RecordScalarAction(const StaticMutexAutoLock& lock, uint32_t aId,
-                                 bool aDynamic, ScalarActionType aAction,
-                                 const ScalarVariant& aValue) {
-  internal_RecordScalarAction(
-      lock,
-      ScalarAction{aId, aDynamic, aAction, Some(aValue), ProcessID::Parent});
-}
-
-/**
- * Record the given action on a keyed scalar into the pending actions list.
- *
- * If the pending actions list overflows the high water mark length
- * all operations are immediately applied, including the passed action.
- *
- * @param aScalarAction The action to record.
- */
-void internal_RecordKeyedScalarAction(const StaticMutexAutoLock& lock,
-                                      const KeyedScalarAction& aScalarAction) {
-  // Make sure to have the storage.
-  if (!gKeyedScalarsActions) {
-    gKeyedScalarsActions = new nsTArray<KeyedScalarAction>();
-  }
-
-  // Store the action.
-  gKeyedScalarsActions->AppendElement(aScalarAction);
-
-  // If this action overflows the pending actions array, we immediately apply
-  // pending operations and assume loading is over. If loading still happens
-  // afterwards, some scalar values might be overwritten and inconsistent, but
-  // we won't lose operations on otherwise untouched probes.
-  if (gKeyedScalarsActions->Length() > kScalarActionsArrayHighWaterMark) {
-    internal_ApplyPendingOperations(lock);
-    return;
-  }
-}
-
-/**
- * Record the given action on a keyed scalar on the main process into the
- * pending actions list.
- *
- * If the pending actions list overflows the high water mark length
- * all operations are immediately applied, including the passed action.
- *
- * @param aId The scalar's ID this action applies to
- * @param aDynamic Determines if the scalar is dynamic
- * @param aKey The scalar's key
- * @param aAction The action to record
- * @param aValue The additional data for the recorded action
- */
-void internal_RecordKeyedScalarAction(const StaticMutexAutoLock& lock,
-                                      uint32_t aId, bool aDynamic,
-                                      const nsAString& aKey,
-                                      ScalarActionType aAction,
-                                      const ScalarVariant& aValue) {
-  internal_RecordKeyedScalarAction(
-      lock,
-      KeyedScalarAction{aId, aDynamic, aAction, NS_ConvertUTF16toUTF8(aKey),
-                        Some(aValue), ProcessID::Parent});
-}
-
 /**
  * Update the scalar with the provided value. This is used by the JS API.
  *
@@ -1655,16 +1476,11 @@ void internal_RecordKeyedScalarAction(const StaticMutexAutoLock& lock,
  * @param aName The scalar name.
  * @param aType The action type for updating the scalar.
  * @param aValue The value to use for updating the scalar.
- * @param aProcessOverride The process for which the scalar must be updated.
- *        This must only be used for GeckoView persistence. It must be
- *        set to the ProcessID::Parent for all the other cases.
- * @param aForce Whether to force updating even if load is in progress.
  * @return a ScalarResult error value.
  */
-ScalarResult internal_UpdateScalar(
-    const StaticMutexAutoLock& lock, const nsACString& aName,
-    ScalarActionType aType, nsIVariant* aValue,
-    ProcessID aProcessOverride = ProcessID::Parent, bool aForce = false) {
+ScalarResult internal_UpdateScalar(const StaticMutexAutoLock& lock,
+                                   const nsACString& aName,
+                                   ScalarActionType aType, nsIVariant* aValue) {
   ScalarKey uniqueId;
   nsresult rv = internal_GetEnumByScalarName(lock, aName, &uniqueId);
   if (NS_FAILED(rv)) {
@@ -1672,7 +1488,7 @@ ScalarResult internal_UpdateScalar(
                                     : ScalarResult::UnknownScalar;
   }
 
-  ScalarResult sr = internal_CanRecordScalar(lock, uniqueId, false, aForce);
+  ScalarResult sr = internal_CanRecordScalar(lock, uniqueId, false, false);
   if (sr != ScalarResult::Ok) {
     if (sr == ScalarResult::CannotRecordDataset) {
       return ScalarResult::Ok;
@@ -1695,23 +1511,9 @@ ScalarResult internal_UpdateScalar(
     return ScalarResult::Ok;
   }
 
-  if (!aForce && internal_IsScalarDeserializing(lock)) {
-    const BaseScalarInfo& info = internal_GetScalarInfo(lock, uniqueId);
-    // Convert the nsIVariant to a Variant.
-    mozilla::Maybe<ScalarVariant> variantValue;
-    sr = GetVariantFromIVariant(aValue, info.kind, variantValue);
-    if (sr != ScalarResult::Ok) {
-      MOZ_ASSERT(false, "Unable to convert nsIVariant to mozilla::Variant.");
-      return sr;
-    }
-    internal_RecordScalarAction(lock, uniqueId.id, uniqueId.dynamic, aType,
-                                variantValue.ref());
-    return ScalarResult::Ok;
-  }
-
   // Finally get the scalar.
   ScalarBase* scalar = nullptr;
-  rv = internal_GetScalarByEnum(lock, uniqueId, aProcessOverride, &scalar);
+  rv = internal_GetScalarByEnum(lock, uniqueId, ProcessID::Parent, &scalar);
   if (NS_FAILED(rv)) {
     // Don't throw on expired scalars.
     if (rv == NS_ERROR_NOT_AVAILABLE) {
@@ -1823,15 +1625,13 @@ nsresult internal_GetKeyedScalarByEnum(const StaticMutexAutoLock& lock,
  * @param aKey The key name.
  * @param aType The action type for updating the scalar.
  * @param aValue The value to use for updating the scalar.
- * @param aProcessOverride The process for which the scalar must be updated.
- *        This must only be used for GeckoView persistence. It must be
- *        set to the ProcessID::Parent for all the other cases.
  * @return a ScalarResult error value.
  */
-ScalarResult internal_UpdateKeyedScalar(
-    const StaticMutexAutoLock& lock, const nsACString& aName,
-    const nsAString& aKey, ScalarActionType aType, nsIVariant* aValue,
-    ProcessID aProcessOverride = ProcessID::Parent, bool aForce = false) {
+ScalarResult internal_UpdateKeyedScalar(const StaticMutexAutoLock& lock,
+                                        const nsACString& aName,
+                                        const nsAString& aKey,
+                                        ScalarActionType aType,
+                                        nsIVariant* aValue) {
   ScalarKey uniqueId;
   nsresult rv = internal_GetEnumByScalarName(lock, aName, &uniqueId);
   if (NS_FAILED(rv)) {
@@ -1839,7 +1639,7 @@ ScalarResult internal_UpdateKeyedScalar(
                                     : ScalarResult::UnknownScalar;
   }
 
-  ScalarResult sr = internal_CanRecordScalar(lock, uniqueId, true, aForce);
+  ScalarResult sr = internal_CanRecordScalar(lock, uniqueId, true, false);
   if (sr != ScalarResult::Ok) {
     if (sr == ScalarResult::CannotRecordDataset) {
       return ScalarResult::Ok;
@@ -1862,23 +1662,10 @@ ScalarResult internal_UpdateKeyedScalar(
     return ScalarResult::Ok;
   }
 
-  if (!aForce && internal_IsScalarDeserializing(lock)) {
-    const BaseScalarInfo& info = internal_GetScalarInfo(lock, uniqueId);
-    // Convert the nsIVariant to a Variant.
-    mozilla::Maybe<ScalarVariant> variantValue;
-    sr = GetVariantFromIVariant(aValue, info.kind, variantValue);
-    if (sr != ScalarResult::Ok) {
-      MOZ_ASSERT(false, "Unable to convert nsIVariant to mozilla::Variant.");
-      return sr;
-    }
-    internal_RecordKeyedScalarAction(lock, uniqueId.id, uniqueId.dynamic, aKey,
-                                     aType, variantValue.ref());
-    return ScalarResult::Ok;
-  }
-
   // Finally get the scalar.
   KeyedScalar* scalar = nullptr;
-  rv = internal_GetKeyedScalarByEnum(lock, uniqueId, aProcessOverride, &scalar);
+  rv =
+      internal_GetKeyedScalarByEnum(lock, uniqueId, ProcessID::Parent, &scalar);
   if (NS_FAILED(rv)) {
     // Don't throw on expired scalars.
     if (rv == NS_ERROR_NOT_AVAILABLE) {
@@ -2392,21 +2179,6 @@ void internal_ApplyKeyedScalarActions(
   }
 }
 
-void internal_ApplyPendingOperations(const StaticMutexAutoLock& lock) {
-  if (gScalarsActions && gScalarsActions->Length() > 0) {
-    internal_ApplyScalarActions(lock, *gScalarsActions);
-    gScalarsActions->Clear();
-  }
-
-  if (gKeyedScalarsActions && gKeyedScalarsActions->Length() > 0) {
-    internal_ApplyKeyedScalarActions(lock, *gKeyedScalarsActions);
-    gKeyedScalarsActions->Clear();
-  }
-
-  // After all pending operations are applied deserialization is done
-  gIsDeserializing = false;
-}
-
 }  // namespace
 
 ////////////////////////////////////////////////////////////////////////
@@ -2477,16 +2249,6 @@ void TelemetryScalar::DeInitializeGlobalState() {
   gInitDone = false;
 }
 
-void TelemetryScalar::DeserializationStarted() {
-  StaticMutexAutoLock locker(gTelemetryScalarsMutex);
-  gIsDeserializing = true;
-}
-
-void TelemetryScalar::ApplyPendingOperations() {
-  StaticMutexAutoLock locker(gTelemetryScalarsMutex);
-  internal_ApplyPendingOperations(locker);
-}
-
 void TelemetryScalar::SetCanRecordBase(bool b) {
   StaticMutexAutoLock locker(gTelemetryScalarsMutex);
   gCanRecordBase = b;
@@ -2596,12 +2358,6 @@ void TelemetryScalar::Add(mozilla::Telemetry::ScalarID aId, uint32_t aValue) {
     return;
   }
 
-  if (internal_IsScalarDeserializing(locker)) {
-    internal_RecordScalarAction(locker, uniqueId.id, uniqueId.dynamic,
-                                ScalarActionType::eAdd, ScalarVariant(aValue));
-    return;
-  }
-
   ScalarBase* scalar = nullptr;
   nsresult rv =
       internal_GetScalarByEnum(locker, uniqueId, ProcessID::Parent, &scalar);
@@ -2642,13 +2398,6 @@ void TelemetryScalar::Add(mozilla::Telemetry::ScalarID aId,
     return;
   }
 
-  if (internal_IsScalarDeserializing(locker)) {
-    internal_RecordKeyedScalarAction(locker, uniqueId.id, uniqueId.dynamic,
-                                     aKey, ScalarActionType::eAdd,
-                                     ScalarVariant(aValue));
-    return;
-  }
-
   KeyedScalar* scalar = nullptr;
   nsresult rv = internal_GetKeyedScalarByEnum(locker, uniqueId,
                                               ProcessID::Parent, &scalar);
@@ -2758,12 +2507,6 @@ void TelemetryScalar::Set(mozilla::Telemetry::ScalarID aId, uint32_t aValue) {
     return;
   }
 
-  if (internal_IsScalarDeserializing(locker)) {
-    internal_RecordScalarAction(locker, uniqueId.id, uniqueId.dynamic,
-                                ScalarActionType::eSet, ScalarVariant(aValue));
-    return;
-  }
-
   ScalarBase* scalar = nullptr;
   nsresult rv =
       internal_GetScalarByEnum(locker, uniqueId, ProcessID::Parent, &scalar);
@@ -2803,13 +2546,6 @@ void TelemetryScalar::Set(mozilla::Telemetry::ScalarID aId,
     return;
   }
 
-  if (internal_IsScalarDeserializing(locker)) {
-    internal_RecordScalarAction(locker, uniqueId.id, uniqueId.dynamic,
-                                ScalarActionType::eSet,
-                                ScalarVariant(nsString(aValue)));
-    return;
-  }
-
   ScalarBase* scalar = nullptr;
   nsresult rv =
       internal_GetScalarByEnum(locker, uniqueId, ProcessID::Parent, &scalar);
@@ -2848,12 +2584,6 @@ void TelemetryScalar::Set(mozilla::Telemetry::ScalarID aId, bool aValue) {
     return;
   }
 
-  if (internal_IsScalarDeserializing(locker)) {
-    internal_RecordScalarAction(locker, uniqueId.id, uniqueId.dynamic,
-                                ScalarActionType::eSet, ScalarVariant(aValue));
-    return;
-  }
-
   ScalarBase* scalar = nullptr;
   nsresult rv =
       internal_GetScalarByEnum(locker, uniqueId, ProcessID::Parent, &scalar);
@@ -2894,13 +2624,6 @@ void TelemetryScalar::Set(mozilla::Telemetry::ScalarID aId,
     return;
   }
 
-  if (internal_IsScalarDeserializing(locker)) {
-    internal_RecordKeyedScalarAction(locker, uniqueId.id, uniqueId.dynamic,
-                                     aKey, ScalarActionType::eSet,
-                                     ScalarVariant(aValue));
-    return;
-  }
-
   KeyedScalar* scalar = nullptr;
   nsresult rv = internal_GetKeyedScalarByEnum(locker, uniqueId,
                                               ProcessID::Parent, &scalar);
@@ -2941,13 +2664,6 @@ void TelemetryScalar::Set(mozilla::Telemetry::ScalarID aId,
     return;
   }
 
-  if (internal_IsScalarDeserializing(locker)) {
-    internal_RecordKeyedScalarAction(locker, uniqueId.id, uniqueId.dynamic,
-                                     aKey, ScalarActionType::eSet,
-                                     ScalarVariant(aValue));
-    return;
-  }
-
   KeyedScalar* scalar = nullptr;
   nsresult rv = internal_GetKeyedScalarByEnum(locker, uniqueId,
                                               ProcessID::Parent, &scalar);
@@ -3061,13 +2777,6 @@ void TelemetryScalar::SetMaximum(mozilla::Telemetry::ScalarID aId,
     return;
   }
 
-  if (internal_IsScalarDeserializing(locker)) {
-    internal_RecordScalarAction(locker, uniqueId.id, uniqueId.dynamic,
-                                ScalarActionType::eSetMaximum,
-                                ScalarVariant(aValue));
-    return;
-  }
-
   ScalarBase* scalar = nullptr;
   nsresult rv =
       internal_GetScalarByEnum(locker, uniqueId, ProcessID::Parent, &scalar);
@@ -3108,13 +2817,6 @@ void TelemetryScalar::SetMaximum(mozilla::Telemetry::ScalarID aId,
     return;
   }
 
-  if (internal_IsScalarDeserializing(locker)) {
-    internal_RecordKeyedScalarAction(locker, uniqueId.id, uniqueId.dynamic,
-                                     aKey, ScalarActionType::eSetMaximum,
-                                     ScalarVariant(aValue));
-    return;
-  }
-
   KeyedScalar* scalar = nullptr;
   nsresult rv = internal_GetKeyedScalarByEnum(locker, uniqueId,
                                               ProcessID::Parent, &scalar);
@@ -3538,8 +3240,6 @@ void TelemetryScalar::ClearScalars() {
   gKeyedScalarStorageMap.Clear();
   gDynamicBuiltinScalarStorageMap.Clear();
   gDynamicBuiltinKeyedScalarStorageMap.Clear();
-  gScalarsActions = nullptr;
-  gKeyedScalarsActions = nullptr;
 }
 
 size_t TelemetryScalar::GetMapShallowSizesOfExcludingThis(
@@ -3580,20 +3280,6 @@ void TelemetryScalar::UpdateChildData(
              "parent process.");
   StaticMutexAutoLock locker(gTelemetryScalarsMutex);
 
-  // If scalars are still being deserialized, we need to record the incoming
-  // operations as well.
-  if (internal_IsScalarDeserializing(locker)) {
-    for (const ScalarAction& action : aScalarActions) {
-      // We're only getting immutable access, so let's copy it
-      ScalarAction copy = action;
-      // Fix up the process type
-      copy.mProcessType = aProcessType;
-      internal_RecordScalarAction(locker, copy);
-    }
-
-    return;
-  }
-
   internal_ApplyScalarActions(locker, aScalarActions, Some(aProcessType));
 }
 
@@ -3605,20 +3291,6 @@ void TelemetryScalar::UpdateChildKeyedData(
              "from the parent process.");
   StaticMutexAutoLock locker(gTelemetryScalarsMutex);
 
-  // If scalars are still being deserialized, we need to record the incoming
-  // operations as well.
-  if (internal_IsScalarDeserializing(locker)) {
-    for (const KeyedScalarAction& action : aScalarActions) {
-      // We're only getting immutable access, so let's copy it
-      KeyedScalarAction copy = action;
-      // Fix up the process type
-      copy.mProcessType = aProcessType;
-      internal_RecordKeyedScalarAction(locker, copy);
-    }
-
-    return;
-  }
-
   internal_ApplyKeyedScalarActions(locker, aScalarActions, Some(aProcessType));
 }
 
@@ -3632,10 +3304,6 @@ void TelemetryScalar::RecordDiscardedData(
     return;
   }
 
-  if (GetCurrentProduct() == SupportedProduct::GeckoviewStreaming) {
-    return;
-  }
-
   ScalarBase* scalar = nullptr;
   mozilla::DebugOnly<nsresult> rv;
 
@@ -3754,437 +3422,3 @@ nsresult TelemetryScalar::GetAllStores(StringHashSet& set) {
 
   return NS_OK;
 }
-
-////////////////////////////////////////////////////////////////////////
-////////////////////////////////////////////////////////////////////////
-//
-// PUBLIC: GeckoView serialization/deserialization functions.
-
-/**
- * Write the scalar data to the provided Json object, for
- * GeckoView measurement persistence. The output format is the same one used
- * for snapshotting the scalars.
- *
- * @param {aWriter} The JSON object to write to.
- * @returns NS_OK or a failure value explaining why persistence failed.
- */
-nsresult TelemetryScalar::SerializeScalars(mozilla::JSONWriter& aWriter) {
-  // Get a copy of the data, without clearing.
-  ScalarSnapshotTable scalarsToReflect;
-  {
-    StaticMutexAutoLock locker(gTelemetryScalarsMutex);
-    // For persistence, we care about all the datasets. Worst case, they
-    // will be empty.
-    nsresult rv = internal_GetScalarSnapshot(
-        locker, scalarsToReflect, nsITelemetry::DATASET_PRERELEASE_CHANNELS,
-        false, /*aClearScalars*/
-        "main"_ns);
-    if (NS_FAILED(rv)) {
-      return rv;
-    }
-  }
-
-  // Persist the scalars to the JSON object.
-  for (const auto& entry : scalarsToReflect) {
-    const ScalarTupleArray& processScalars = entry.GetData();
-    const char* processName = GetNameForProcessID(ProcessID(entry.GetKey()));
-
-    aWriter.StartObjectProperty(mozilla::MakeStringSpan(processName));
-
-    for (const ScalarDataTuple& scalar : processScalars) {
-      nsresult rv = WriteVariantToJSONWriter(
-          std::get<2>(scalar) /*aScalarType*/,
-          std::get<1>(scalar) /*aInputValue*/,
-          mozilla::MakeStringSpan(std::get<0>(scalar)) /*aPropertyName*/,
-          aWriter /*aWriter*/);
-      if (NS_FAILED(rv)) {
-        // Skip this scalar if we failed to write it. We don't bail out just
-        // yet as we may salvage other scalars. We eventually need to call
-        // EndObject.
-        continue;
-      }
-    }
-
-    aWriter.EndObject();
-  }
-
-  return NS_OK;
-}
-
-/**
- * Write the keyed scalar data to the provided Json object, for
- * GeckoView measurement persistence. The output format is the same
- * one used for snapshotting the keyed scalars.
- *
- * @param {aWriter} The JSON object to write to.
- * @returns NS_OK or a failure value explaining why persistence failed.
- */
-nsresult TelemetryScalar::SerializeKeyedScalars(mozilla::JSONWriter& aWriter) {
-  // Get a copy of the data, without clearing.
-  KeyedScalarSnapshotTable keyedScalarsToReflect;
-  {
-    StaticMutexAutoLock locker(gTelemetryScalarsMutex);
-    // For persistence, we care about all the datasets. Worst case, they
-    // will be empty.
-    nsresult rv = internal_GetKeyedScalarSnapshot(
-        locker, keyedScalarsToReflect,
-        nsITelemetry::DATASET_PRERELEASE_CHANNELS, false, /*aClearScalars*/
-        "main"_ns);
-    if (NS_FAILED(rv)) {
-      return rv;
-    }
-  }
-
-  // Persist the scalars to the JSON object.
-  for (const auto& entry : keyedScalarsToReflect) {
-    const KeyedScalarTupleArray& processScalars = entry.GetData();
-    const char* processName = GetNameForProcessID(ProcessID(entry.GetKey()));
-
-    aWriter.StartObjectProperty(mozilla::MakeStringSpan(processName));
-
-    for (const KeyedScalarDataTuple& keyedScalarData : processScalars) {
-      aWriter.StartObjectProperty(
-          mozilla::MakeStringSpan(std::get<0>(keyedScalarData)));
-
-      // Define a property for each scalar key, then add it to the keyed scalar
-      // object.
-      const nsTArray<KeyedScalar::KeyValuePair>& keyProps =
-          std::get<1>(keyedScalarData);
-      for (const KeyedScalar::KeyValuePair& keyData : keyProps) {
-        nsresult rv = WriteVariantToJSONWriter(
-            std::get<2>(keyedScalarData) /*aScalarType*/,
-            keyData.second /*aInputValue*/,
-            PromiseFlatCString(keyData.first) /*aOutKey*/, aWriter /*aWriter*/);
-        if (NS_FAILED(rv)) {
-          // Skip this scalar if we failed to write it. We don't bail out just
-          // yet as we may salvage other scalars. We eventually need to call
-          // EndObject.
-          continue;
-        }
-      }
-      aWriter.EndObject();
-    }
-    aWriter.EndObject();
-  }
-
-  return NS_OK;
-}
-
-/**
- * Load the persisted measurements from a Json object and inject them
- * in the relevant process storage.
- *
- * @param {aData} The input Json object.
- * @returns NS_OK if loading was performed, an error code explaining the
- *          failure reason otherwise.
- */
-nsresult TelemetryScalar::DeserializePersistedScalars(
-    JSContext* aCx, JS::Handle<JS::Value> aData) {
-  MOZ_ASSERT(XRE_IsParentProcess(), "Only load scalars in the parent process");
-  if (!XRE_IsParentProcess()) {
-    return NS_ERROR_FAILURE;
-  }
-
-  typedef std::pair<nsCString, nsCOMPtr<nsIVariant>> PersistedScalarPair;
-  typedef nsTArray<PersistedScalarPair> PersistedScalarArray;
-  typedef nsTHashMap<ProcessIDHashKey, PersistedScalarArray>
-      PeristedScalarStorage;
-
-  PeristedScalarStorage scalarsToUpdate;
-
-  // Before updating the scalars, we need to get the data out of the JS
-  // wrappers. We can't hold the scalars mutex while handling JS stuff.
-  // Build a <scalar name, value> map.
-  JS::Rooted<JSObject*> scalarDataObj(aCx, &aData.toObject());
-  JS::Rooted<JS::IdVector> processes(aCx, JS::IdVector(aCx));
-  if (!JS_Enumerate(aCx, scalarDataObj, &processes)) {
-    // We can't even enumerate the processes in the loaded data, so
-    // there is nothing we could recover from the persistence file. Bail out.
-    JS_ClearPendingException(aCx);
-    return NS_ERROR_FAILURE;
-  }
-
-  // The following block of code attempts to extract as much data as possible
-  // from the serialized JSON, even in case of light data corruptions: if, for
-  // example, the data for a single process is corrupted or is in an unexpected
-  // form, we press on and attempt to load the data for the other processes.
-  JS::Rooted<JS::PropertyKey> process(aCx);
-  for (auto& processVal : processes) {
-    // This is required as JS API calls require an Handle<jsid> and not a
-    // plain jsid.
-    process = processVal;
-    // Get the process name.
-    nsAutoJSString processNameJS;
-    if (!processNameJS.init(aCx, process)) {
-      JS_ClearPendingException(aCx);
-      continue;
-    }
-
-    // Make sure it's valid. Note that this is safe to call outside
-    // of a locked section.
-    NS_ConvertUTF16toUTF8 processName(processNameJS);
-    ProcessID processID = GetIDForProcessName(processName.get());
-    if (processID == ProcessID::Count) {
-      NS_WARNING(
-          nsPrintfCString("Failed to get process ID for %s", processName.get())
-              .get());
-      continue;
-    }
-
-    // And its probes.
-    JS::Rooted<JS::Value> processData(aCx);
-    if (!JS_GetPropertyById(aCx, scalarDataObj, process, &processData)) {
-      JS_ClearPendingException(aCx);
-      continue;
-    }
-
-    if (!processData.isObject()) {
-      // |processData| should be an object containing scalars. If this is
-      // not the case, silently skip and try to load the data for the other
-      // processes.
-      continue;
-    }
-
-    // Iterate through each scalar.
-    JS::Rooted<JSObject*> processDataObj(aCx, &processData.toObject());
-    JS::Rooted<JS::IdVector> scalars(aCx, JS::IdVector(aCx));
-    if (!JS_Enumerate(aCx, processDataObj, &scalars)) {
-      JS_ClearPendingException(aCx);
-      continue;
-    }
-
-    JS::Rooted<JS::PropertyKey> scalar(aCx);
-    for (auto& scalarVal : scalars) {
-      scalar = scalarVal;
-      // Get the scalar name.
-      nsAutoJSString scalarName;
-      if (!scalarName.init(aCx, scalar)) {
-        JS_ClearPendingException(aCx);
-        continue;
-      }
-
-      // Get the scalar value as a JS value.
-      JS::Rooted<JS::Value> scalarValue(aCx);
-      if (!JS_GetPropertyById(aCx, processDataObj, scalar, &scalarValue)) {
-        JS_ClearPendingException(aCx);
-        continue;
-      }
-
-      if (scalarValue.isNullOrUndefined()) {
-        // We can't set scalars to null or undefined values, skip this
-        // and try to load other scalars.
-        continue;
-      }
-
-      // Unpack the aVal to nsIVariant.
-      nsCOMPtr<nsIVariant> unpackedVal;
-      nsresult rv = nsContentUtils::XPConnect()->JSToVariant(
-          aCx, scalarValue, getter_AddRefs(unpackedVal));
-      if (NS_FAILED(rv)) {
-        JS_ClearPendingException(aCx);
-        continue;
-      }
-
-      // Add the scalar to the map.
-      PersistedScalarArray& processScalars =
-          scalarsToUpdate.LookupOrInsert(static_cast<uint32_t>(processID));
-      processScalars.AppendElement(std::make_pair(
-          nsCString(NS_ConvertUTF16toUTF8(scalarName)), unpackedVal));
-    }
-  }
-
-  // Now that all the JS specific operations are finished, update the scalars.
-  {
-    StaticMutexAutoLock lock(gTelemetryScalarsMutex);
-
-    for (const auto& entry : scalarsToUpdate) {
-      const PersistedScalarArray& processScalars = entry.GetData();
-      for (PersistedScalarArray::size_type i = 0; i < processScalars.Length();
-           i++) {
-        mozilla::Unused << internal_UpdateScalar(
-            lock, processScalars[i].first, ScalarActionType::eSet,
-            processScalars[i].second, ProcessID(entry.GetKey()),
-            true /* aForce */);
-      }
-    }
-  }
-
-  return NS_OK;
-}
-
-/**
- * Load the persisted measurements from a Json object and injects them
- * in the relevant process storage.
- *
- * @param {aData} The input Json object.
- * @returns NS_OK if loading was performed, an error code explaining the
- *          failure reason otherwise.
- */
-nsresult TelemetryScalar::DeserializePersistedKeyedScalars(
-    JSContext* aCx, JS::Handle<JS::Value> aData) {
-  MOZ_ASSERT(XRE_IsParentProcess(), "Only load scalars in the parent process");
-  if (!XRE_IsParentProcess()) {
-    return NS_ERROR_FAILURE;
-  }
-
-  typedef std::tuple<nsCString, nsString, nsCOMPtr<nsIVariant>>
-      PersistedKeyedScalarTuple;
-  typedef nsTArray<PersistedKeyedScalarTuple> PersistedKeyedScalarArray;
-  typedef nsTHashMap<ProcessIDHashKey, PersistedKeyedScalarArray>
-      PeristedKeyedScalarStorage;
-
-  PeristedKeyedScalarStorage scalarsToUpdate;
-
-  // Before updating the keyed scalars, we need to get the data out of the JS
-  // wrappers. We can't hold the scalars mutex while handling JS stuff.
-  // Build a <scalar name, value> map.
-  JS::Rooted<JSObject*> scalarDataObj(aCx, &aData.toObject());
-  JS::Rooted<JS::IdVector> processes(aCx, JS::IdVector(aCx));
-  if (!JS_Enumerate(aCx, scalarDataObj, &processes)) {
-    // We can't even enumerate the processes in the loaded data, so
-    // there is nothing we could recover from the persistence file. Bail out.
-    JS_ClearPendingException(aCx);
-    return NS_ERROR_FAILURE;
-  }
-
-  // The following block of code attempts to extract as much data as possible
-  // from the serialized JSON, even in case of light data corruptions: if, for
-  // example, the data for a single process is corrupted or is in an unexpected
-  // form, we press on and attempt to load the data for the other processes.
-  JS::Rooted<JS::PropertyKey> process(aCx);
-  for (auto& processVal : processes) {
-    process = processVal;
-    // Get the process name.
-    nsAutoJSString processNameJS;
-    if (!processNameJS.init(aCx, process)) {
-      JS_ClearPendingException(aCx);
-      continue;
-    }
-
-    // Make sure it's valid. Note that this is safe to call outside
-    // of a locked section.
-    NS_ConvertUTF16toUTF8 processName(processNameJS);
-    ProcessID processID = GetIDForProcessName(processName.get());
-    if (processID == ProcessID::Count) {
-      NS_WARNING(
-          nsPrintfCString("Failed to get process ID for %s", processName.get())
-              .get());
-      continue;
-    }
-
-    // And its probes.
-    JS::Rooted<JS::Value> processData(aCx);
-    if (!JS_GetPropertyById(aCx, scalarDataObj, process, &processData)) {
-      JS_ClearPendingException(aCx);
-      continue;
-    }
-
-    if (!processData.isObject()) {
-      // |processData| should be an object containing scalars. If this is
-      // not the case, silently skip and try to load the data for the other
-      // processes.
-      continue;
-    }
-
-    // Iterate through each keyed scalar.
-    JS::Rooted<JSObject*> processDataObj(aCx, &processData.toObject());
-    JS::Rooted<JS::IdVector> keyedScalars(aCx, JS::IdVector(aCx));
-    if (!JS_Enumerate(aCx, processDataObj, &keyedScalars)) {
-      JS_ClearPendingException(aCx);
-      continue;
-    }
-
-    JS::Rooted<JS::PropertyKey> keyedScalar(aCx);
-    for (auto& keyedScalarVal : keyedScalars) {
-      keyedScalar = keyedScalarVal;
-      // Get the scalar name.
-      nsAutoJSString scalarName;
-      if (!scalarName.init(aCx, keyedScalar)) {
-        JS_ClearPendingException(aCx);
-        continue;
-      }
-
-      // Get the data for this keyed scalar.
-      JS::Rooted<JS::Value> keyedScalarData(aCx);
-      if (!JS_GetPropertyById(aCx, processDataObj, keyedScalar,
-                              &keyedScalarData)) {
-        JS_ClearPendingException(aCx);
-        continue;
-      }
-
-      if (!keyedScalarData.isObject()) {
-        // Keyed scalar data need to be an object. If that's not the case, skip
-        // it and try to load the rest of the data.
-        continue;
-      }
-
-      // Get the keys in the keyed scalar.
-      JS::Rooted<JSObject*> keyedScalarDataObj(aCx,
-                                               &keyedScalarData.toObject());
-      JS::Rooted<JS::IdVector> keys(aCx, JS::IdVector(aCx));
-      if (!JS_Enumerate(aCx, keyedScalarDataObj, &keys)) {
-        JS_ClearPendingException(aCx);
-        continue;
-      }
-
-      JS::Rooted<JS::PropertyKey> key(aCx);
-      for (auto keyVal : keys) {
-        key = keyVal;
-        // Get the process name.
-        nsAutoJSString keyName;
-        if (!keyName.init(aCx, key)) {
-          JS_ClearPendingException(aCx);
-          continue;
-        }
-
-        // Get the scalar value as a JS value.
-        JS::Rooted<JS::Value> scalarValue(aCx);
-        if (!JS_GetPropertyById(aCx, keyedScalarDataObj, key, &scalarValue)) {
-          JS_ClearPendingException(aCx);
-          continue;
-        }
-
-        if (scalarValue.isNullOrUndefined()) {
-          // We can't set scalars to null or undefined values, skip this
-          // and try to load other scalars.
-          continue;
-        }
-
-        // Unpack the aVal to nsIVariant.
-        nsCOMPtr<nsIVariant> unpackedVal;
-        nsresult rv = nsContentUtils::XPConnect()->JSToVariant(
-            aCx, scalarValue, getter_AddRefs(unpackedVal));
-        if (NS_FAILED(rv)) {
-          JS_ClearPendingException(aCx);
-          continue;
-        }
-
-        // Add the scalar to the map.
-        PersistedKeyedScalarArray& processScalars =
-            scalarsToUpdate.LookupOrInsert(static_cast<uint32_t>(processID));
-        processScalars.AppendElement(
-            std::make_tuple(nsCString(NS_ConvertUTF16toUTF8(scalarName)),
-                            nsString(keyName), unpackedVal));
-      }
-    }
-  }
-
-  // Now that all the JS specific operations are finished, update the scalars.
-  {
-    StaticMutexAutoLock lock(gTelemetryScalarsMutex);
-
-    for (const auto& entry : scalarsToUpdate) {
-      const PersistedKeyedScalarArray& processScalars = entry.GetData();
-      for (PersistedKeyedScalarArray::size_type i = 0;
-           i < processScalars.Length(); i++) {
-        mozilla::Unused << internal_UpdateKeyedScalar(
-            lock, std::get<0>(processScalars[i]),
-            std::get<1>(processScalars[i]), ScalarActionType::eSet,
-            std::get<2>(processScalars[i]), ProcessID(entry.GetKey()),
-            true /* aForce */);
-      }
-    }
-  }
-
-  return NS_OK;
-}
diff --git a/toolkit/components/telemetry/core/TelemetryScalar.h b/toolkit/components/telemetry/core/TelemetryScalar.h
index c7e5352860..d45d12cca5 100644
--- a/toolkit/components/telemetry/core/TelemetryScalar.h
+++ b/toolkit/components/telemetry/core/TelemetryScalar.h
@@ -18,8 +18,6 @@
 // For the public interface to Telemetry functionality, see Telemetry.h.
 
 namespace mozilla {
-// This is only used for the GeckoView persistence.
-class JSONWriter;
 namespace Telemetry {
 struct ScalarAction;
 struct KeyedScalarAction;
@@ -112,22 +110,6 @@ void AddDynamicScalarDefinitions(
  * This includes dynamic stores.
  */
 nsresult GetAllStores(mozilla::Telemetry::Common::StringHashSet& set);
-
-// They are responsible for updating in-memory probes with the data persisted
-// on the disk and vice-versa.
-nsresult SerializeScalars(mozilla::JSONWriter& aWriter);
-nsresult SerializeKeyedScalars(mozilla::JSONWriter& aWriter);
-nsresult DeserializePersistedScalars(JSContext* aCx,
-                                     JS::Handle<JS::Value> aData);
-nsresult DeserializePersistedKeyedScalars(JSContext* aCx,
-                                          JS::Handle<JS::Value> aData);
-// Mark deserialization as in progress.
-// After this, all scalar operations are recorded into the pending operations
-// list.
-void DeserializationStarted();
-// Apply all operations from the pending operations list and mark
-// deserialization finished afterwards.
-void ApplyPendingOperations();
 }  // namespace TelemetryScalar
 
 #endif  // TelemetryScalar_h__
diff --git a/toolkit/components/telemetry/dap/DAPTelemetrySender.sys.mjs b/toolkit/components/telemetry/dap/DAPTelemetrySender.sys.mjs
index 9dcc949788..b948e80681 100644
--- a/toolkit/components/telemetry/dap/DAPTelemetrySender.sys.mjs
+++ b/toolkit/components/telemetry/dap/DAPTelemetrySender.sys.mjs
@@ -35,7 +35,12 @@ XPCOMUtils.defineLazyPreferenceGetter(lazy, "HELPER", PREF_HELPER, undefined);
  */
 
 export const DAPTelemetrySender = new (class {
-  startup() {
+  async startup() {
+    await lazy.NimbusFeatures.dapTelemetry.ready();
+    if (!lazy.NimbusFeatures.dapTelemetry.getVariable("enabled")) {
+      return;
+    }
+
     lazy.logConsole.debug("Performing DAP startup");
 
     if (lazy.NimbusFeatures.dapTelemetry.getVariable("visitCountingEnabled")) {
diff --git a/toolkit/components/telemetry/dap/ffi-gtest/Cargo.toml b/toolkit/components/telemetry/dap/ffi-gtest/Cargo.toml
index abad140b7d..3abbb9d60c 100644
--- a/toolkit/components/telemetry/dap/ffi-gtest/Cargo.toml
+++ b/toolkit/components/telemetry/dap/ffi-gtest/Cargo.toml
@@ -11,7 +11,7 @@ edition = "2021"
 [dependencies]
 dap_ffi = { path = "../ffi" }
 hex = { version = "0.4.3", features = ["serde"] }
-prio = {version = "0.15.3", default-features = false }
+prio = {version = "0.16.2", default-features = false }
 serde = { version = "1.0", features = ["derive"] }
 serde_json = { version = "1.0" }
 thin-vec = { version = "0.2.1", features = ["gecko-ffi"] }
diff --git a/toolkit/components/telemetry/dap/ffi-gtest/test.rs b/toolkit/components/telemetry/dap/ffi-gtest/test.rs
index 3871965107..874e0e99a5 100644
--- a/toolkit/components/telemetry/dap/ffi-gtest/test.rs
+++ b/toolkit/components/telemetry/dap/ffi-gtest/test.rs
@@ -17,7 +17,7 @@ use prio::codec::{Decode, Encode};
 pub extern "C" fn dap_test_encoding() {
     let r = Report::new_dummy();
     let mut encoded = Vec::<u8>::new();
-    Report::encode(&r, &mut encoded);
+    Report::encode(&r, &mut encoded).expect("Report encoding failed!");
     let decoded = Report::decode(&mut Cursor::new(&encoded)).expect("Report decoding failed!");
     if r != decoded {
         println!("Report:");
diff --git a/toolkit/components/telemetry/dap/ffi/Cargo.toml b/toolkit/components/telemetry/dap/ffi/Cargo.toml
index dfb69e4821..5e94bf30a7 100644
--- a/toolkit/components/telemetry/dap/ffi/Cargo.toml
+++ b/toolkit/components/telemetry/dap/ffi/Cargo.toml
@@ -8,6 +8,7 @@ authors = [
 license = "MPL-2.0"
 
 [dependencies]
-prio = {version = "0.15.3", default-features = false }
+prio = {version = "0.16.2", default-features = false }
 thin-vec = { version = "0.2.1", features = ["gecko-ffi"] }
 rand = "0.8"
+log = "0.4"
diff --git a/toolkit/components/telemetry/dap/ffi/src/lib.rs b/toolkit/components/telemetry/dap/ffi/src/lib.rs
index 998c8af204..2d595c1a8f 100644
--- a/toolkit/components/telemetry/dap/ffi/src/lib.rs
+++ b/toolkit/components/telemetry/dap/ffi/src/lib.rs
@@ -5,6 +5,8 @@
 use std::error::Error;
 use std::io::Cursor;
 
+use log::{debug, warn};
+
 use prio::vdaf::prio3::Prio3Sum;
 use prio::vdaf::prio3::Prio3SumVec;
 use thin_vec::ThinVec;
@@ -19,8 +21,6 @@ use types::Time;
 
 use prio::codec::Encode;
 use prio::codec::{decode_u16_items, encode_u32_items};
-use prio::flp::types::{Sum, SumVec};
-use prio::vdaf::prio3::Prio3;
 use prio::vdaf::Client;
 use prio::vdaf::VdafError;
 
@@ -41,7 +41,7 @@ extern "C" {
     ) -> bool;
 }
 
-pub fn new_prio_u8(num_aggregators: u8, bits: u32) -> Result<Prio3Sum, VdafError> {
+pub fn new_prio_sum(num_aggregators: u8, bits: usize) -> Result<Prio3Sum, VdafError> {
     if bits > 64 {
         return Err(VdafError::Uncategorized(format!(
             "bit length ({}) exceeds limit for aggregate type (64)",
@@ -49,17 +49,16 @@ pub fn new_prio_u8(num_aggregators: u8, bits: u32) -> Result<Prio3Sum, VdafError
         )));
     }
 
-    Prio3::new(num_aggregators, Sum::new(bits as usize)?)
+    Prio3Sum::new_sum(num_aggregators, bits)
 }
 
-pub fn new_prio_vecu8(num_aggregators: u8, len: usize) -> Result<Prio3SumVec, VdafError> {
+pub fn new_prio_sumvec(
+    num_aggregators: u8,
+    len: usize,
+    bits: usize,
+) -> Result<Prio3SumVec, VdafError> {
     let chunk_length = prio::vdaf::prio3::optimal_chunk_length(8 * len);
-    Prio3::new(num_aggregators, SumVec::new(8, len, chunk_length)?)
-}
-
-pub fn new_prio_vecu16(num_aggregators: u8, len: usize) -> Result<Prio3SumVec, VdafError> {
-    let chunk_length = prio::vdaf::prio3::optimal_chunk_length(16 * len);
-    Prio3::new(num_aggregators, SumVec::new(16, len, chunk_length)?)
+    Prio3SumVec::new_sum_vec(num_aggregators, bits, len, chunk_length)
 }
 
 enum Role {
@@ -112,14 +111,17 @@ impl Shardable for u8 {
         &self,
         nonce: &[u8; 16],
     ) -> Result<(Vec<u8>, Vec<Vec<u8>>), Box<dyn std::error::Error>> {
-        let prio = new_prio_u8(2, 2)?;
+        let prio = new_prio_sum(2, 8)?;
 
         let (public_share, input_shares) = prio.shard(&(*self as u128), nonce)?;
 
         debug_assert_eq!(input_shares.len(), 2);
 
-        let encoded_input_shares = input_shares.iter().map(|s| s.get_encoded()).collect();
-        let encoded_public_share = public_share.get_encoded();
+        let encoded_input_shares = input_shares
+            .iter()
+            .map(|s| s.get_encoded())
+            .collect::<Result<Vec<_>, _>>()?;
+        let encoded_public_share = public_share.get_encoded()?;
         Ok((encoded_public_share, encoded_input_shares))
     }
 }
@@ -129,15 +131,18 @@ impl Shardable for ThinVec<u8> {
         &self,
         nonce: &[u8; 16],
     ) -> Result<(Vec<u8>, Vec<Vec<u8>>), Box<dyn std::error::Error>> {
-        let prio = new_prio_vecu8(2, self.len())?;
+        let prio = new_prio_sumvec(2, self.len(), 8)?;
 
         let measurement: Vec<u128> = self.iter().map(|e| (*e as u128)).collect();
         let (public_share, input_shares) = prio.shard(&measurement, nonce)?;
 
         debug_assert_eq!(input_shares.len(), 2);
 
-        let encoded_input_shares = input_shares.iter().map(|s| s.get_encoded()).collect();
-        let encoded_public_share = public_share.get_encoded();
+        let encoded_input_shares = input_shares
+            .iter()
+            .map(|s| s.get_encoded())
+            .collect::<Result<Vec<_>, _>>()?;
+        let encoded_public_share = public_share.get_encoded()?;
         Ok((encoded_public_share, encoded_input_shares))
     }
 }
@@ -147,15 +152,18 @@ impl Shardable for ThinVec<u16> {
         &self,
         nonce: &[u8; 16],
     ) -> Result<(Vec<u8>, Vec<Vec<u8>>), Box<dyn std::error::Error>> {
-        let prio = new_prio_vecu16(2, self.len())?;
+        let prio = new_prio_sumvec(2, self.len(), 16)?;
 
         let measurement: Vec<u128> = self.iter().map(|e| (*e as u128)).collect();
         let (public_share, input_shares) = prio.shard(&measurement, nonce)?;
 
         debug_assert_eq!(input_shares.len(), 2);
 
-        let encoded_input_shares = input_shares.iter().map(|s| s.get_encoded()).collect();
-        let encoded_public_share = public_share.get_encoded();
+        let encoded_input_shares = input_shares
+            .iter()
+            .map(|s| s.get_encoded())
+            .collect::<Result<Vec<_>, _>>()?;
+        let encoded_public_share = public_share.get_encoded()?;
         Ok((encoded_public_share, encoded_input_shares))
     }
 }
@@ -163,7 +171,7 @@ impl Shardable for ThinVec<u16> {
 /// Pre-fill the info part of the HPKE sealing with the constants from the standard.
 fn make_base_info() -> Vec<u8> {
     let mut info = Vec::<u8>::new();
-    const START: &[u8] = "dap-07 input share".as_bytes();
+    const START: &[u8] = "dap-09 input share".as_bytes();
     info.extend(START);
     const FIXED: u8 = 1;
     info.push(FIXED);
@@ -215,7 +223,8 @@ fn get_dap_report_internal<T: Shardable>(
             }
             .get_encoded()
         })
-        .collect();
+        .collect::<Result<Vec<_>, _>>()?;
+    debug!("Plaintext input shares computed.");
 
     let metadata = ReportMetadata {
         report_id,
@@ -230,18 +239,20 @@ fn get_dap_report_internal<T: Shardable>(
     let mut info = make_base_info();
 
     let mut aad = Vec::from(*task_id);
-    metadata.encode(&mut aad);
-    encode_u32_items(&mut aad, &(), &encoded_public_share);
+    metadata.encode(&mut aad)?;
+    encode_u32_items(&mut aad, &(), &encoded_public_share)?;
 
     info.push(Role::Leader as u8);
 
     let leader_payload =
         hpke_encrypt_wrapper(&plaintext_input_shares[0], &aad, &info, &leader_hpke_config)?;
+    debug!("Leader payload encrypted.");
 
     *info.last_mut().unwrap() = Role::Helper as u8;
 
     let helper_payload =
         hpke_encrypt_wrapper(&plaintext_input_shares[1], &aad, &info, &helper_hpke_config)?;
+    debug!("Helper payload encrypted.");
 
     Ok(Report {
         metadata,
@@ -264,20 +275,22 @@ pub extern "C" fn dapGetReportU8(
 ) -> bool {
     assert_eq!(task_id.len(), 32);
 
-    if let Ok(report) = get_dap_report_internal::<u8>(
+    let Ok(report) = get_dap_report_internal::<u8>(
         leader_hpke_config_encoded,
         helper_hpke_config_encoded,
         &measurement,
         &task_id.as_slice().try_into().unwrap(),
         time_precision,
-    ) {
-        let encoded_report = report.get_encoded();
-        out_report.extend(encoded_report);
-
-        true
-    } else {
-        false
-    }
+    ) else {
+        warn!("Creating report failed!");
+        return false;
+    };
+    let Ok(encoded_report) = report.get_encoded() else {
+        warn!("Encoding report failed!");
+        return false;
+    };
+    out_report.extend(encoded_report);
+    true
 }
 
 #[no_mangle]
@@ -291,20 +304,22 @@ pub extern "C" fn dapGetReportVecU8(
 ) -> bool {
     assert_eq!(task_id.len(), 32);
 
-    if let Ok(report) = get_dap_report_internal::<ThinVec<u8>>(
+    let Ok(report) = get_dap_report_internal::<ThinVec<u8>>(
         leader_hpke_config_encoded,
         helper_hpke_config_encoded,
         measurement,
         &task_id.as_slice().try_into().unwrap(),
         time_precision,
-    ) {
-        let encoded_report = report.get_encoded();
-        out_report.extend(encoded_report);
-
-        true
-    } else {
-        false
-    }
+    ) else {
+        warn!("Creating report failed!");
+        return false;
+    };
+    let Ok(encoded_report) = report.get_encoded() else {
+        warn!("Encoding report failed!");
+        return false;
+    };
+    out_report.extend(encoded_report);
+    true
 }
 
 #[no_mangle]
@@ -318,18 +333,20 @@ pub extern "C" fn dapGetReportVecU16(
 ) -> bool {
     assert_eq!(task_id.len(), 32);
 
-    if let Ok(report) = get_dap_report_internal::<ThinVec<u16>>(
+    let Ok(report) = get_dap_report_internal::<ThinVec<u16>>(
         leader_hpke_config_encoded,
         helper_hpke_config_encoded,
         measurement,
         &task_id.as_slice().try_into().unwrap(),
         time_precision,
-    ) {
-        let encoded_report = report.get_encoded();
-        out_report.extend(encoded_report);
-
-        true
-    } else {
-        false
-    }
+    ) else {
+        warn!("Creating report failed!");
+        return false;
+    };
+    let Ok(encoded_report) = report.get_encoded() else {
+        warn!("Encoding report failed!");
+        return false;
+    };
+    out_report.extend(encoded_report);
+    true
 }
diff --git a/toolkit/components/telemetry/dap/ffi/src/types.rs b/toolkit/components/telemetry/dap/ffi/src/types.rs
index e8f6385dcd..c84cbf16bc 100644
--- a/toolkit/components/telemetry/dap/ffi/src/types.rs
+++ b/toolkit/components/telemetry/dap/ffi/src/types.rs
@@ -34,8 +34,9 @@ impl Decode for TaskID {
 }
 
 impl Encode for TaskID {
-    fn encode(&self, bytes: &mut Vec<u8>) {
+    fn encode(&self, bytes: &mut Vec<u8>) -> Result<(), CodecError> {
         bytes.extend_from_slice(&self.0);
+        Ok(())
     }
 }
 
@@ -52,8 +53,9 @@ impl Decode for Time {
 }
 
 impl Encode for Time {
-    fn encode(&self, bytes: &mut Vec<u8>) {
-        u64::encode(&self.0, bytes);
+    fn encode(&self, bytes: &mut Vec<u8>) -> Result<(), CodecError> {
+        u64::encode(&self.0, bytes)?;
+        Ok(())
     }
 }
 
@@ -93,9 +95,10 @@ impl Decode for Extension {
 }
 
 impl Encode for Extension {
-    fn encode(&self, bytes: &mut Vec<u8>) {
-        (self.extension_type as u16).encode(bytes);
-        encode_u16_items(bytes, &(), &self.extension_data);
+    fn encode(&self, bytes: &mut Vec<u8>) -> Result<(), CodecError> {
+        (self.extension_type as u16).encode(bytes)?;
+        encode_u16_items(bytes, &(), &self.extension_data)?;
+        Ok(())
     }
 }
 
@@ -131,9 +134,10 @@ pub struct PlaintextInputShare {
 }
 
 impl Encode for PlaintextInputShare {
-    fn encode(&self, bytes: &mut Vec<u8>) {
-        encode_u16_items(bytes, &(), &self.extensions);
-        encode_u32_items(bytes, &(), &self.payload);
+    fn encode(&self, bytes: &mut Vec<u8>) -> Result<(), CodecError> {
+        encode_u16_items(bytes, &(), &self.extensions)?;
+        encode_u32_items(bytes, &(), &self.payload)?;
+        Ok(())
     }
 }
 
@@ -150,8 +154,9 @@ impl Decode for HpkeConfigId {
 }
 
 impl Encode for HpkeConfigId {
-    fn encode(&self, bytes: &mut Vec<u8>) {
-        self.0.encode(bytes);
+    fn encode(&self, bytes: &mut Vec<u8>) -> Result<(), CodecError> {
+        self.0.encode(bytes)?;
+        Ok(())
     }
 }
 
@@ -189,12 +194,13 @@ impl Decode for HpkeConfig {
 }
 
 impl Encode for HpkeConfig {
-    fn encode(&self, bytes: &mut Vec<u8>) {
-        self.id.encode(bytes);
-        self.kem_id.encode(bytes);
-        self.kdf_id.encode(bytes);
-        self.aead_id.encode(bytes);
-        encode_u16_items(bytes, &(), &self.public_key);
+    fn encode(&self, bytes: &mut Vec<u8>) -> Result<(), CodecError> {
+        self.id.encode(bytes)?;
+        self.kem_id.encode(bytes)?;
+        self.kdf_id.encode(bytes)?;
+        self.aead_id.encode(bytes)?;
+        encode_u16_items(bytes, &(), &self.public_key)?;
+        Ok(())
     }
 }
 
@@ -227,10 +233,11 @@ impl Decode for HpkeCiphertext {
 }
 
 impl Encode for HpkeCiphertext {
-    fn encode(&self, bytes: &mut Vec<u8>) {
-        self.config_id.encode(bytes);
-        encode_u16_items(bytes, &(), &self.enc);
-        encode_u32_items(bytes, &(), &self.payload);
+    fn encode(&self, bytes: &mut Vec<u8>) -> Result<(), CodecError> {
+        self.config_id.encode(bytes)?;
+        encode_u16_items(bytes, &(), &self.enc)?;
+        encode_u32_items(bytes, &(), &self.payload)?;
+        Ok(())
     }
 }
 
@@ -248,8 +255,9 @@ impl Decode for ReportID {
 }
 
 impl Encode for ReportID {
-    fn encode(&self, bytes: &mut Vec<u8>) {
+    fn encode(&self, bytes: &mut Vec<u8>) -> Result<(), CodecError> {
         bytes.extend_from_slice(&self.0);
+        Ok(())
     }
 }
 
@@ -286,9 +294,10 @@ impl Decode for ReportMetadata {
 }
 
 impl Encode for ReportMetadata {
-    fn encode(&self, bytes: &mut Vec<u8>) {
-        self.report_id.encode(bytes);
-        self.time.encode(bytes);
+    fn encode(&self, bytes: &mut Vec<u8>) -> Result<(), CodecError> {
+        self.report_id.encode(bytes)?;
+        self.time.encode(bytes)?;
+        Ok(())
     }
 }
 
@@ -307,7 +316,6 @@ pub struct Report {
     pub helper_encrypted_input_share: HpkeCiphertext,
 }
 
-
 impl Report {
     /// Creates a minimal report for use in tests.
     pub fn new_dummy() -> Self {
@@ -321,8 +329,16 @@ impl Report {
                 time: Time::generate(1),
             },
             public_share: vec![],
-            leader_encrypted_input_share: HpkeCiphertext { config_id: HpkeConfigId(5), enc: vec![1, 2, 3, 4, 5], payload: vec![6, 7, 8, 9, 10] },
-            helper_encrypted_input_share: HpkeCiphertext { config_id: HpkeConfigId(100), enc: enc.into(), payload: payload.into() },
+            leader_encrypted_input_share: HpkeCiphertext {
+                config_id: HpkeConfigId(5),
+                enc: vec![1, 2, 3, 4, 5],
+                payload: vec![6, 7, 8, 9, 10],
+            },
+            helper_encrypted_input_share: HpkeCiphertext {
+                config_id: HpkeConfigId(100),
+                enc: enc.into(),
+                payload: payload.into(),
+            },
         }
     }
 }
@@ -349,10 +365,11 @@ impl Decode for Report {
 }
 
 impl Encode for Report {
-    fn encode(&self, bytes: &mut Vec<u8>) {
-        self.metadata.encode(bytes);
-        encode_u32_items(bytes, &(), &self.public_share);
-        self.leader_encrypted_input_share.encode(bytes);
-        self.helper_encrypted_input_share.encode(bytes);
+    fn encode(&self, bytes: &mut Vec<u8>) -> Result<(), CodecError> {
+        self.metadata.encode(bytes)?;
+        encode_u32_items(bytes, &(), &self.public_share)?;
+        self.leader_encrypted_input_share.encode(bytes)?;
+        self.helper_encrypted_input_share.encode(bytes)?;
+        Ok(())
     }
 }
diff --git a/toolkit/components/telemetry/dap/tests/xpcshell/test_dap.js b/toolkit/components/telemetry/dap/tests/xpcshell/test_dap.js
index deb68bafef..ba973c647f 100644
--- a/toolkit/components/telemetry/dap/tests/xpcshell/test_dap.js
+++ b/toolkit/components/telemetry/dap/tests/xpcshell/test_dap.js
@@ -91,7 +91,7 @@ function uploadHandler(request, response) {
   console.log(body.available());
   Assert.equal(
     true,
-    body.available() == 406 || body.available() == 3654,
+    body.available() == 886 || body.available() == 3654,
     "Wrong request body size."
   );
   received = true;
diff --git a/toolkit/components/telemetry/docs/data/environment.rst b/toolkit/components/telemetry/docs/data/environment.rst
index 9e966fe707..6b0649bda7 100644
--- a/toolkit/components/telemetry/docs/data/environment.rst
+++ b/toolkit/components/telemetry/docs/data/environment.rst
@@ -104,6 +104,7 @@ Structure:
         creationDate: <integer>, // integer days since UNIX epoch, e.g. 16446
         resetDate: <integer>, // integer days since UNIX epoch, e.g. 16446 - optional
         firstUseDate: <integer>, // integer days since UNIX epoch, e.g. 16446 - optional
+        recoveredFromBackup: <integer>, // integer days since UNIX epoch, e.g. 16446 - optional
       },
       partner: { // This section may not be immediately available on startup
         distributionId: <string>, // pref "distribution.id", null on failure
@@ -281,7 +282,7 @@ Structure:
             hasBinaryComponents: <bool>,
             installDay: <number>, // days since UNIX epoch, 0 on failure
             updateDay: <number>, // days since UNIX epoch, 0 on failure
-            signedState: <integer>, // whether the add-on is signed by AMO, only present for extensions
+            signedState: <integer>, // whether the add-on is signed by AMO
             signedTypes: <string>, // JSON-stringified array of signature types found (see nsIAppSignatureInfo's SignatureAlgorithm enum)
             isSystem: <bool>, // true if this is a System Add-on
             isWebExtension: <bool>, // true if this is a WebExtension
@@ -302,6 +303,8 @@ Structure:
           hasBinaryComponents: <bool>
           installDay: <number>, // days since UNIX epoch, 0 on failure
           updateDay: <number>, // days since UNIX epoch, 0 on failure
+          signedState: <integer>, // whether the add-on is signed by AMO
+          signedTypes: <string>, // JSON-stringified array of signature types found (see nsIAppSignatureInfo's SignatureAlgorithm enum)
         },
         activeGMPlugins: {
             <gmp id>: {
@@ -547,6 +550,13 @@ The time of the first use of profile. If this is an old profile where we can't
 determine this this field will not be present.
 It's read from a file-stored timestamp from the client's profile directory.
 
+recoveredFromBackup
+~~~~~~~~~~~~~~~~~~~
+
+The time that this profile was recovered from a backup. If the profile was never
+recovered from a backup, this field will not be present.
+It's read from a file-stored timestamp from the client's profile directory.
+
 partner
 -------
 
diff --git a/toolkit/components/telemetry/docs/internals/preferences.rst b/toolkit/components/telemetry/docs/internals/preferences.rst
index 0c63ae031d..1ce8647322 100644
--- a/toolkit/components/telemetry/docs/internals/preferences.rst
+++ b/toolkit/components/telemetry/docs/internals/preferences.rst
@@ -202,26 +202,6 @@ Data-choices notification
 
   This is the only channel-specific version that we currently use for the minimum policy version.
 
-GeckoView
----------
-
-``toolkit.telemetry.geckoview.streaming``
-
-   Whether the GeckoView mode we're running in is the variety that uses the :doc:`GeckoView Streaming Telemetry API <../internals/geckoview-streaming>` or not.
-   Defaults to false.
-
-``toolkit.telemetry.geckoview.batchDurationMS``
-
-   The duration in milliseconds over which :doc:`GeckoView Streaming Telemetry <../internals/geckoview-streaming>` will batch accumulations before passing it on to its delegate.
-   Defaults to 5000.
-
-``toolkit.telemetry.geckoview.maxBatchStalenessMS``
-
-   The maximum time (in milliseconds) between flushes of the
-   :doc:`GeckoView Streaming Telemetry <../internals/geckoview-streaming>`
-   batch to its delegate.
-   Defaults to 60000.
-
 Testing
 -------
 
diff --git a/toolkit/components/telemetry/docs/internals/review.rst b/toolkit/components/telemetry/docs/internals/review.rst
index 80a3bd57de..d38bcfcc3b 100644
--- a/toolkit/components/telemetry/docs/internals/review.rst
+++ b/toolkit/components/telemetry/docs/internals/review.rst
@@ -67,7 +67,7 @@ Considerations for all changes
 - Does this affect products more broadly than expected?
 
   - Consider all our platforms: Windows, Mac, Linux, Android.
-  - Consider all our products: Firefox, Fennec, GeckoView, Glean.
+  - Consider all our products: Firefox, Fenix, Glean.
 
 - Does this fall afoul of common architectural failures?
 
diff --git a/toolkit/components/telemetry/geckoview/gtest/TestGeckoViewStreaming.cpp b/toolkit/components/telemetry/geckoview/gtest/TestGeckoViewStreaming.cpp
deleted file mode 100644
index ebaa7099a8..0000000000
--- a/toolkit/components/telemetry/geckoview/gtest/TestGeckoViewStreaming.cpp
+++ /dev/null
@@ -1,237 +0,0 @@
-/* vim:set ts=2 sw=2 sts=2 et: */
-/* Any copyright is dedicated to the Public Domain.
- * http://creativecommons.org/publicdomain/zero/1.0/
- */
-
-#include "gmock/gmock.h"
-#include "gtest/gtest.h"
-#include "mozilla/gtest/MozAssertions.h"
-#include "mozilla/Preferences.h"
-#include "mozilla/Services.h"
-#include "mozilla/Telemetry.h"
-#include "nsIObserverService.h"
-#include "nsThreadUtils.h"
-#include "TelemetryFixture.h"
-#include "TelemetryTestHelpers.h"
-#include "streaming/GeckoViewStreamingTelemetry.h"
-
-using namespace mozilla;
-using namespace mozilla::Telemetry;
-using namespace TelemetryTestHelpers;
-using GeckoViewStreamingTelemetry::StreamingTelemetryDelegate;
-using mozilla::Telemetry::ScalarID;
-using ::testing::_;
-using ::testing::Eq;
-using ::testing::StrictMock;
-
-namespace {
-
-const char* kGeckoViewStreamingPref = "toolkit.telemetry.geckoview.streaming";
-const char* kBatchTimeoutPref = "toolkit.telemetry.geckoview.batchDurationMS";
-
-constexpr auto kTestHgramName = "TELEMETRY_TEST_STREAMING"_ns;
-constexpr auto kTestHgramName2 = "TELEMETRY_TEST_STREAMING_2"_ns;
-constexpr auto kTestCategoricalName = "TELEMETRY_TEST_CATEGORICAL_OPTOUT"_ns;
-const HistogramID kTestHgram = Telemetry::TELEMETRY_TEST_STREAMING;
-const HistogramID kTestHgram2 = Telemetry::TELEMETRY_TEST_STREAMING_2;
-
-class TelemetryStreamingFixture : public TelemetryTestFixture {
- protected:
-  virtual void SetUp() {
-    TelemetryTestFixture::SetUp();
-    Preferences::SetBool(kGeckoViewStreamingPref, true);
-    Preferences::SetInt(kBatchTimeoutPref, 5000);
-  }
-  virtual void TearDown() {
-    TelemetryTestFixture::TearDown();
-    Preferences::SetBool(kGeckoViewStreamingPref, false);
-    GeckoViewStreamingTelemetry::RegisterDelegate(nullptr);
-  }
-};
-
-class MockDelegate : public StreamingTelemetryDelegate {
- public:
-  MOCK_METHOD2(ReceiveHistogramSamples,
-               void(const nsCString& aHistogramName,
-                    const nsTArray<uint32_t>& aSamples));
-  MOCK_METHOD2(ReceiveCategoricalHistogramSamples,
-               void(const nsCString& aHistogramName,
-                    const nsTArray<uint32_t>& aSamples));
-  MOCK_METHOD2(ReceiveBoolScalarValue,
-               void(const nsCString& aScalarName, bool aValue));
-  MOCK_METHOD2(ReceiveStringScalarValue,
-               void(const nsCString& aScalarName, const nsCString& aValue));
-  MOCK_METHOD2(ReceiveUintScalarValue,
-               void(const nsCString& aScalarName, uint32_t aValue));
-};  // class MockDelegate
-
-TEST_F(TelemetryStreamingFixture, HistogramSamples) {
-  const uint32_t kSampleOne = 401;
-  const uint32_t kSampleTwo = 2019;
-
-  CopyableTArray<uint32_t> samplesArray;
-  samplesArray.AppendElement(kSampleOne);
-  samplesArray.AppendElement(kSampleTwo);
-
-  auto md = MakeRefPtr<MockDelegate>();
-  EXPECT_CALL(*md, ReceiveHistogramSamples(Eq(kTestHgramName),
-                                           Eq(std::move(samplesArray))));
-  GeckoViewStreamingTelemetry::RegisterDelegate(md);
-
-  Telemetry::Accumulate(Telemetry::TELEMETRY_TEST_STREAMING, kSampleOne);
-  Preferences::SetInt(kBatchTimeoutPref, 0);
-  Telemetry::Accumulate(Telemetry::TELEMETRY_TEST_STREAMING, kSampleTwo);
-}
-
-TEST_F(TelemetryStreamingFixture, CategoricalHistogramSamples) {
-  auto kSampleOne =
-      Telemetry::LABELS_TELEMETRY_TEST_CATEGORICAL_OPTOUT::CommonLabel;
-  auto kSampleTwo = Telemetry::LABELS_TELEMETRY_TEST_CATEGORICAL_OPTOUT::Label5;
-
-  CopyableTArray<uint32_t> samplesArray;
-  samplesArray.AppendElement(static_cast<uint32_t>(kSampleOne));
-  samplesArray.AppendElement(static_cast<uint32_t>(kSampleOne));
-  samplesArray.AppendElement(static_cast<uint32_t>(kSampleTwo));
-
-  auto md = MakeRefPtr<MockDelegate>();
-  EXPECT_CALL(*md, ReceiveCategoricalHistogramSamples(
-                       Eq(kTestCategoricalName), Eq(std::move(samplesArray))));
-  GeckoViewStreamingTelemetry::RegisterDelegate(md);
-
-  Telemetry::AccumulateCategorical(kSampleOne);
-  Telemetry::AccumulateCategorical(kSampleOne);
-  Preferences::SetInt(kBatchTimeoutPref, 0);
-  Telemetry::AccumulateCategorical(kSampleTwo);
-}
-
-TEST_F(TelemetryStreamingFixture, MultipleHistograms) {
-  const uint32_t kSample1 = 400;
-  const uint32_t kSample2 = 1 << 31;
-  const uint32_t kSample3 = 7;
-  CopyableTArray<uint32_t> samplesArray1;
-  samplesArray1.AppendElement(kSample1);
-  samplesArray1.AppendElement(kSample2);
-  CopyableTArray<uint32_t> samplesArray2;
-  samplesArray2.AppendElement(kSample3);
-
-  auto md = MakeRefPtr<MockDelegate>();
-  EXPECT_CALL(*md, ReceiveHistogramSamples(Eq(kTestHgramName),
-                                           Eq(std::move(samplesArray1))));
-  EXPECT_CALL(*md, ReceiveHistogramSamples(Eq(kTestHgramName2),
-                                           Eq(std::move(samplesArray2))));
-
-  GeckoViewStreamingTelemetry::RegisterDelegate(md);
-
-  Telemetry::Accumulate(kTestHgram, kSample1);
-  Telemetry::Accumulate(kTestHgram2, kSample3);
-  Preferences::SetInt(kBatchTimeoutPref, 0);
-  Telemetry::Accumulate(kTestHgram, kSample2);
-}
-
-// If we can find a way to convert the expectation's arg into an stl container,
-// we can use gmock's own ::testing::UnorderedElementsAre() instead.
-auto MatchUnordered(uint32_t sample1, uint32_t sample2) {
-  CopyableTArray<uint32_t> samplesArray1;
-  samplesArray1.AppendElement(sample1);
-  samplesArray1.AppendElement(sample2);
-
-  CopyableTArray<uint32_t> samplesArray2;
-  samplesArray2.AppendElement(sample2);
-  samplesArray2.AppendElement(sample1);
-
-  return ::testing::AnyOf(Eq(std::move(samplesArray1)),
-                          Eq(std::move(samplesArray2)));
-}
-
-TEST_F(TelemetryStreamingFixture, MultipleThreads) {
-  const uint32_t kSample1 = 4;
-  const uint32_t kSample2 = 14;
-
-  auto md = MakeRefPtr<MockDelegate>();
-  // In this test, samples for the second test hgram are uninteresting.
-  EXPECT_CALL(*md, ReceiveHistogramSamples(Eq(kTestHgramName2), _));
-  EXPECT_CALL(*md, ReceiveHistogramSamples(Eq(kTestHgramName),
-                                           MatchUnordered(kSample1, kSample2)));
-
-  GeckoViewStreamingTelemetry::RegisterDelegate(md);
-
-  nsCOMPtr<nsIThread> t1;
-  nsCOMPtr<nsIThread> t2;
-  nsCOMPtr<nsIThread> t3;
-
-  nsCOMPtr<nsIRunnable> r1 = NS_NewRunnableFunction(
-      "accumulate 4", [&]() { Telemetry::Accumulate(kTestHgram, kSample1); });
-  nsCOMPtr<nsIRunnable> r2 = NS_NewRunnableFunction(
-      "accumulate 14", [&]() { Telemetry::Accumulate(kTestHgram, kSample2); });
-
-  nsresult rv = NS_NewNamedThread("t1", getter_AddRefs(t1), r1);
-  EXPECT_NS_SUCCEEDED(rv);
-  rv = NS_NewNamedThread("t2", getter_AddRefs(t2), r2);
-  EXPECT_NS_SUCCEEDED(rv);
-
-  // Give the threads a chance to do their work.
-  PR_Sleep(PR_MillisecondsToInterval(1));
-
-  Preferences::SetInt(kBatchTimeoutPref, 0);
-  Telemetry::Accumulate(kTestHgram2, kSample1);
-}
-
-TEST_F(TelemetryStreamingFixture, ScalarValues) {
-  constexpr auto kBoolScalarName = "telemetry.test.boolean_kind"_ns;
-  constexpr auto kStringScalarName = "telemetry.test.string_kind"_ns;
-  constexpr auto kUintScalarName = "telemetry.test.unsigned_int_kind"_ns;
-
-  const bool kBoolScalarValue = true;
-  constexpr auto kStringScalarValue = "a string scalar value"_ns;
-  const uint32_t kUintScalarValue = 42;
-
-  auto md = MakeRefPtr<MockDelegate>();
-  EXPECT_CALL(
-      *md, ReceiveBoolScalarValue(Eq(kBoolScalarName), Eq(kBoolScalarValue)));
-  EXPECT_CALL(*md, ReceiveStringScalarValue(Eq(kStringScalarName),
-                                            Eq(kStringScalarValue)));
-  EXPECT_CALL(
-      *md, ReceiveUintScalarValue(Eq(kUintScalarName), Eq(kUintScalarValue)));
-
-  GeckoViewStreamingTelemetry::RegisterDelegate(md);
-
-  Telemetry::ScalarSet(ScalarID::TELEMETRY_TEST_BOOLEAN_KIND, kBoolScalarValue);
-  Telemetry::ScalarSet(ScalarID::TELEMETRY_TEST_STRING_KIND,
-                       NS_ConvertUTF8toUTF16(kStringScalarValue));
-  Preferences::SetInt(kBatchTimeoutPref,
-                      0);  // Trigger batch on next accumulation.
-  Telemetry::ScalarSet(ScalarID::TELEMETRY_TEST_UNSIGNED_INT_KIND,
-                       kUintScalarValue);
-}
-
-TEST_F(TelemetryStreamingFixture, ExpiredHistogram) {
-  const HistogramID kExpiredHistogram = Telemetry::TELEMETRY_TEST_EXPIRED;
-  const uint32_t kSample = 401;
-
-  // Strict Mock fails on any method calls.
-  auto md = MakeRefPtr<StrictMock<MockDelegate>>();
-  GeckoViewStreamingTelemetry::RegisterDelegate(md);
-
-  Preferences::SetInt(kBatchTimeoutPref, 0);
-  Telemetry::Accumulate(kExpiredHistogram, kSample);
-}
-
-TEST_F(TelemetryStreamingFixture, SendOnAppBackground) {
-  constexpr auto kBoolScalarName = "telemetry.test.boolean_kind"_ns;
-  const bool kBoolScalarValue = true;
-  const char* kApplicationBackgroundTopic = "application-background";
-
-  auto md = MakeRefPtr<MockDelegate>();
-  EXPECT_CALL(
-      *md, ReceiveBoolScalarValue(Eq(kBoolScalarName), Eq(kBoolScalarValue)));
-
-  GeckoViewStreamingTelemetry::RegisterDelegate(md);
-  Telemetry::ScalarSet(ScalarID::TELEMETRY_TEST_BOOLEAN_KIND, kBoolScalarValue);
-
-  nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
-  ASSERT_TRUE(!!os)
-  << "Observer Service unavailable?!?!";
-  os->NotifyObservers(nullptr, kApplicationBackgroundTopic, nullptr);
-}
-
-}  // namespace
diff --git a/toolkit/components/telemetry/geckoview/gtest/moz.build b/toolkit/components/telemetry/geckoview/gtest/moz.build
deleted file mode 100644
index eb6a2f9293..0000000000
--- a/toolkit/components/telemetry/geckoview/gtest/moz.build
+++ /dev/null
@@ -1,28 +0,0 @@
-# -*- Mode: python; c-basic-offset: 4; indent-tabs-mode: nil; tab-width: 40 -*-
-# vim: set filetype=python:
-# 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/.
-
-Library("telemetrygeckoviewtest")
-
-LOCAL_INCLUDES += [
-    "../",
-    "../..",
-    "../../..",
-    "/toolkit/components/telemetry/tests/gtest",
-    "/xpcom/io",
-]
-
-# GeckoView Streaming Telemetry is only available on Android.
-if CONFIG["MOZ_WIDGET_TOOLKIT"] == "android":
-    UNIFIED_SOURCES += [
-        "TestGeckoViewStreaming.cpp",
-    ]
-
-# We need the following line otherwise including
-# "TelemetryHistogram.h" in tests will fail due to
-# missing headers.
-include("/ipc/chromium/chromium-config.mozbuild")
-
-FINAL_LIBRARY = "xul-gtest"
diff --git a/toolkit/components/telemetry/geckoview/streaming/GeckoViewStreamingTelemetry.cpp b/toolkit/components/telemetry/geckoview/streaming/GeckoViewStreamingTelemetry.cpp
deleted file mode 100644
index 6c4b9590c0..0000000000
--- a/toolkit/components/telemetry/geckoview/streaming/GeckoViewStreamingTelemetry.cpp
+++ /dev/null
@@ -1,282 +0,0 @@
-/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/* vim: set ts=8 sts=2 et sw=2 tw=80: */
-/* 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/. */
-
-#include "GeckoViewStreamingTelemetry.h"
-
-#include "mozilla/Assertions.h"
-#include "mozilla/Services.h"
-#include "mozilla/StaticMutex.h"
-#include "mozilla/StaticPtr.h"
-#include "mozilla/StaticPrefs_toolkit.h"
-#include "mozilla/TimeStamp.h"
-#include "nsTHashMap.h"
-#include "nsIObserver.h"
-#include "nsIObserverService.h"
-#include "nsITimer.h"
-#include "nsTArray.h"
-#include "nsThreadUtils.h"
-
-using mozilla::Runnable;
-using mozilla::StaticMutex;
-using mozilla::StaticMutexAutoLock;
-using mozilla::StaticRefPtr;
-using mozilla::TimeStamp;
-
-// Batches and streams Telemetry samples to a JNI delegate which will
-// (presumably) do something with the data. Expected to be used to route data
-// up to the Android Components layer to be translated into Glean metrics.
-namespace GeckoViewStreamingTelemetry {
-
-class LifecycleObserver;
-void SendBatch(const StaticMutexAutoLock& aLock);
-
-// Topic on which we flush the batch.
-static const char* const kApplicationBackgroundTopic = "application-background";
-
-static StaticMutex gMutex MOZ_UNANNOTATED;
-
-// -- The following state is accessed across threads.
-// -- Do not touch these if you do not hold gMutex.
-
-// The time the batch began.
-TimeStamp gBatchBegan;
-// The batch of histograms and samples.
-typedef nsTHashMap<nsCStringHashKey, nsTArray<uint32_t>> HistogramBatch;
-HistogramBatch gBatch;
-HistogramBatch gCategoricalBatch;
-// The batches of Scalars and their values.
-typedef nsTHashMap<nsCStringHashKey, bool> BoolScalarBatch;
-BoolScalarBatch gBoolScalars;
-typedef nsTHashMap<nsCStringHashKey, nsCString> StringScalarBatch;
-StringScalarBatch gStringScalars;
-typedef nsTHashMap<nsCStringHashKey, uint32_t> UintScalarBatch;
-UintScalarBatch gUintScalars;
-// The delegate to receive the samples and values.
-StaticRefPtr<StreamingTelemetryDelegate> gDelegate;
-// Lifecycle observer used to flush the batch when backgrounded.
-StaticRefPtr<LifecycleObserver> gObserver;
-
-// -- End of gMutex-protected thread-unsafe-accessed data
-
-// Timer that ensures data in the batch never gets too stale.
-// This timer may only be manipulated on the Main Thread.
-StaticRefPtr<nsITimer> gJICTimer;
-
-class LifecycleObserver final : public nsIObserver {
- public:
-  NS_DECL_ISUPPORTS
-  NS_DECL_NSIOBSERVER
-
-  LifecycleObserver() = default;
-
- protected:
-  ~LifecycleObserver() = default;
-};
-
-NS_IMPL_ISUPPORTS(LifecycleObserver, nsIObserver);
-
-NS_IMETHODIMP
-LifecycleObserver::Observe(nsISupports* aSubject, const char* aTopic,
-                           const char16_t* aData) {
-  if (!strcmp(aTopic, kApplicationBackgroundTopic)) {
-    StaticMutexAutoLock lock(gMutex);
-    SendBatch(lock);
-  }
-  return NS_OK;
-}
-
-void RegisterDelegate(const RefPtr<StreamingTelemetryDelegate>& aDelegate) {
-  StaticMutexAutoLock lock(gMutex);
-  gDelegate = aDelegate;
-}
-
-class SendBatchRunnable : public Runnable {
- public:
-  explicit SendBatchRunnable(RefPtr<StreamingTelemetryDelegate> aDelegate,
-                             HistogramBatch&& aBatch,
-                             HistogramBatch&& aCategoricalBatch,
-                             BoolScalarBatch&& aBoolScalars,
-                             StringScalarBatch&& aStringScalars,
-                             UintScalarBatch&& aUintScalars)
-      : Runnable("SendBatchRunnable"),
-        mDelegate(std::move(aDelegate)),
-        mBatch(std::move(aBatch)),
-        mCategoricalBatch(std::move(aCategoricalBatch)),
-        mBoolScalars(std::move(aBoolScalars)),
-        mStringScalars(std::move(aStringScalars)),
-        mUintScalars(std::move(aUintScalars)) {}
-
-  NS_IMETHOD Run() override {
-    MOZ_ASSERT(NS_IsMainThread());
-    MOZ_ASSERT(mDelegate);
-
-    if (gJICTimer) {
-      gJICTimer->Cancel();
-    }
-
-    for (const auto& entry : mBatch) {
-      const nsCString& histogramName = PromiseFlatCString(entry.GetKey());
-      const nsTArray<uint32_t>& samples = entry.GetData();
-
-      mDelegate->ReceiveHistogramSamples(histogramName, samples);
-    }
-    mBatch.Clear();
-
-    for (const auto& entry : mCategoricalBatch) {
-      const nsCString& histogramName = PromiseFlatCString(entry.GetKey());
-      const nsTArray<uint32_t>& samples = entry.GetData();
-
-      mDelegate->ReceiveCategoricalHistogramSamples(histogramName, samples);
-    }
-    mCategoricalBatch.Clear();
-
-    for (const auto& entry : mBoolScalars) {
-      const nsCString& scalarName = PromiseFlatCString(entry.GetKey());
-      mDelegate->ReceiveBoolScalarValue(scalarName, entry.GetData());
-    }
-    mBoolScalars.Clear();
-
-    for (const auto& entry : mStringScalars) {
-      const nsCString& scalarName = PromiseFlatCString(entry.GetKey());
-      const nsCString& scalarValue = PromiseFlatCString(entry.GetData());
-      mDelegate->ReceiveStringScalarValue(scalarName, scalarValue);
-    }
-    mStringScalars.Clear();
-
-    for (const auto& entry : mUintScalars) {
-      const nsCString& scalarName = PromiseFlatCString(entry.GetKey());
-      mDelegate->ReceiveUintScalarValue(scalarName, entry.GetData());
-    }
-    mUintScalars.Clear();
-
-    return NS_OK;
-  }
-
- private:
-  RefPtr<StreamingTelemetryDelegate> mDelegate;
-  HistogramBatch mBatch;
-  HistogramBatch mCategoricalBatch;
-  BoolScalarBatch mBoolScalars;
-  StringScalarBatch mStringScalars;
-  UintScalarBatch mUintScalars;
-};  // class SendBatchRunnable
-
-// Can be called on any thread.
-// NOTE: Pay special attention to what you call in this method as if it
-// accumulates to a gv-streaming-enabled probe we will deadlock the calling
-// thread.
-void SendBatch(const StaticMutexAutoLock& aLock) {
-  if (!gDelegate) {
-    NS_WARNING(
-        "Being asked to send Streaming Telemetry with no registered Streaming "
-        "Telemetry Delegate. Will try again later.");
-    // Give us another full Batch Duration to register a delegate.
-    gBatchBegan = TimeStamp::Now();
-    return;
-  }
-
-  // To make it so accumulations within the delegation don't deadlock us,
-  // move the batches' contents into the Runner.
-  HistogramBatch histogramCopy;
-  gBatch.SwapElements(histogramCopy);
-  HistogramBatch categoricalCopy;
-  gCategoricalBatch.SwapElements(categoricalCopy);
-  BoolScalarBatch boolScalarCopy;
-  gBoolScalars.SwapElements(boolScalarCopy);
-  StringScalarBatch stringScalarCopy;
-  gStringScalars.SwapElements(stringScalarCopy);
-  UintScalarBatch uintScalarCopy;
-  gUintScalars.SwapElements(uintScalarCopy);
-  RefPtr<SendBatchRunnable> runnable = new SendBatchRunnable(
-      gDelegate, std::move(histogramCopy), std::move(categoricalCopy),
-      std::move(boolScalarCopy), std::move(stringScalarCopy),
-      std::move(uintScalarCopy));
-
-  // To make things easier for the delegate, dispatch to the main thread.
-  NS_DispatchToMainThread(runnable);
-}
-
-// Can be called on any thread.
-void BatchCheck(const StaticMutexAutoLock& aLock) {
-  if (!gObserver) {
-    gObserver = new LifecycleObserver();
-    nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
-    if (os) {
-      os->AddObserver(gObserver, kApplicationBackgroundTopic, false);
-    }
-  }
-  if (gBatchBegan.IsNull()) {
-    // Time to begin a new batch.
-    gBatchBegan = TimeStamp::Now();
-    // Set a just-in-case timer to enforce an upper-bound on batch staleness.
-    NS_DispatchToMainThread(NS_NewRunnableFunction(
-        "GeckoviewStreamingTelemetry::ArmTimer", []() -> void {
-          if (!gJICTimer) {
-            gJICTimer = NS_NewTimer().take();
-          }
-          if (gJICTimer) {
-            gJICTimer->InitWithNamedFuncCallback(
-                [](nsITimer*, void*) -> void {
-                  StaticMutexAutoLock locker(gMutex);
-                  SendBatch(locker);
-                },
-                nullptr,
-                mozilla::StaticPrefs::
-                    toolkit_telemetry_geckoview_maxBatchStalenessMS(),
-                nsITimer::TYPE_ONE_SHOT_LOW_PRIORITY,
-                "GeckoviewStreamingTelemetry::SendBatch");
-          }
-        }));
-  }
-  double batchDurationMs = (TimeStamp::Now() - gBatchBegan).ToMilliseconds();
-  if (batchDurationMs >
-      mozilla::StaticPrefs::toolkit_telemetry_geckoview_batchDurationMS()) {
-    SendBatch(aLock);
-    gBatchBegan = TimeStamp();
-  }
-}
-
-// Can be called on any thread.
-void HistogramAccumulate(const nsCString& aName, bool aIsCategorical,
-                         uint32_t aValue) {
-  StaticMutexAutoLock lock(gMutex);
-
-  if (aIsCategorical) {
-    nsTArray<uint32_t>& samples = gCategoricalBatch.LookupOrInsert(aName);
-    samples.AppendElement(aValue);
-  } else {
-    nsTArray<uint32_t>& samples = gBatch.LookupOrInsert(aName);
-    samples.AppendElement(aValue);
-  }
-
-  BatchCheck(lock);
-}
-
-void BoolScalarSet(const nsCString& aName, bool aValue) {
-  StaticMutexAutoLock lock(gMutex);
-
-  gBoolScalars.InsertOrUpdate(aName, aValue);
-
-  BatchCheck(lock);
-}
-
-void StringScalarSet(const nsCString& aName, const nsCString& aValue) {
-  StaticMutexAutoLock lock(gMutex);
-
-  gStringScalars.InsertOrUpdate(aName, aValue);
-
-  BatchCheck(lock);
-}
-
-void UintScalarSet(const nsCString& aName, uint32_t aValue) {
-  StaticMutexAutoLock lock(gMutex);
-
-  gUintScalars.InsertOrUpdate(aName, aValue);
-
-  BatchCheck(lock);
-}
-
-}  // namespace GeckoViewStreamingTelemetry
diff --git a/toolkit/components/telemetry/geckoview/streaming/GeckoViewStreamingTelemetry.h b/toolkit/components/telemetry/geckoview/streaming/GeckoViewStreamingTelemetry.h
deleted file mode 100644
index 458224a3c2..0000000000
--- a/toolkit/components/telemetry/geckoview/streaming/GeckoViewStreamingTelemetry.h
+++ /dev/null
@@ -1,55 +0,0 @@
-/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/* vim: set ts=8 sts=2 et sw=2 tw=80: */
-/* 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/. */
-
-#ifndef GeckoViewStreamingTelemetry_h__
-#define GeckoViewStreamingTelemetry_h__
-
-#include "mozilla/Assertions.h"
-#include "mozilla/RefPtr.h"
-#include "nsISupports.h"
-#include "nsStringFwd.h"
-#include "nsTArray.h"
-
-#include <cstdint>
-
-namespace GeckoViewStreamingTelemetry {
-
-void HistogramAccumulate(const nsCString& aName, bool aIsCategorical,
-                         uint32_t aValue);
-
-void BoolScalarSet(const nsCString& aName, bool aValue);
-void StringScalarSet(const nsCString& aName, const nsCString& aValue);
-void UintScalarSet(const nsCString& aName, uint32_t aValue);
-
-// Classes wishing to receive Streaming Telemetry must implement this interface
-// and register themselves via RegisterDelegate.
-class StreamingTelemetryDelegate {
- public:
-  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(StreamingTelemetryDelegate)
-
-  // Receive* methods will be called from time to time on the main thread.
-  virtual void ReceiveHistogramSamples(const nsCString& aName,
-                                       const nsTArray<uint32_t>& aSamples) = 0;
-  virtual void ReceiveCategoricalHistogramSamples(
-      const nsCString& aName, const nsTArray<uint32_t>& aSamples) = 0;
-  virtual void ReceiveBoolScalarValue(const nsCString& aName, bool aValue) = 0;
-  virtual void ReceiveStringScalarValue(const nsCString& aName,
-                                        const nsCString& aValue) = 0;
-  virtual void ReceiveUintScalarValue(const nsCString& aName,
-                                      uint32_t aValue) = 0;
-
- protected:
-  virtual ~StreamingTelemetryDelegate() = default;
-};
-
-// Registers the provided StreamingTelemetryDelegate to receive Streaming
-// Telemetry, overwriting any previous delegate registration.
-// Call on any thread.
-void RegisterDelegate(const RefPtr<StreamingTelemetryDelegate>& aDelegate);
-
-}  // namespace GeckoViewStreamingTelemetry
-
-#endif  // GeckoViewStreamingTelemetry_h__
diff --git a/toolkit/components/telemetry/geckoview/streaming/metrics.yaml b/toolkit/components/telemetry/geckoview/streaming/metrics.yaml
deleted file mode 100644
index 2386fb2171..0000000000
--- a/toolkit/components/telemetry/geckoview/streaming/metrics.yaml
+++ /dev/null
@@ -1,13 +0,0 @@
-# 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/.
-
-# This file defines the metrics that are recorded by the Glean SDK. They are
-# automatically converted to platform-specific code at build time using the
-# `glean_parser` PyPI package.
-
-# Adding a new metric? Please don't!
-# (At least not without the permission of a Telemetry Module Peer)
-
----
-$schema: moz://mozilla.org/schemas/glean/metrics/2-0-0
diff --git a/toolkit/components/telemetry/moz.build b/toolkit/components/telemetry/moz.build
index 718120cf78..6da23fa372 100644
--- a/toolkit/components/telemetry/moz.build
+++ b/toolkit/components/telemetry/moz.build
@@ -30,9 +30,7 @@ with Files("docs/**"):
     SCHEDULES.exclusive = ["docs"]
 
 if CONFIG["ENABLE_TESTS"]:
-    # We used to need GeckoView tests as a separate directory. This
-    # is no longer true and we could probably move it to tests/gtest.
-    DIRS += ["geckoview/gtest", "tests/gtest"]
+    DIRS += ["tests/gtest"]
 
 TEST_DIRS += ["tests", "dap/ffi-gtest"]
 
@@ -78,7 +76,6 @@ SOURCES += [
     "core/TelemetryScalar.cpp",
     "core/TelemetryUserInteraction.cpp",
     "dap/DAPTelemetry.cpp",
-    "geckoview/streaming/GeckoViewStreamingTelemetry.cpp",
     "other/CombinedStacks.cpp",
     "other/ProcessedStack.cpp",
     "other/TelemetryIOInterposeObserver.cpp",
@@ -244,18 +241,6 @@ GeneratedFile(
     inputs=processes_files,
 )
 
-# Ensure that the GeckoView metrics file parses correctly prior to it
-# being released in Android components. This triggers glean_parser by
-# pretending to generate a file named 'glean_checks'.
-# While this currently only applies to Android, in the medium-term it
-# is going to generate code for Firefox as well (project FOG).
-# Prior art for this was in bug 1063728, within SpiderMonkey tests.
-GeneratedFile(
-    "glean_checks",
-    script="build_scripts/run_glean_parser.py",
-    inputs=["geckoview/streaming/metrics.yaml"],
-)
-
 # Generate UserInteraction file
 userinteraction_files = [
     "UserInteractions.yaml",
diff --git a/toolkit/components/telemetry/tests/gtest/TestScalars.cpp b/toolkit/components/telemetry/tests/gtest/TestScalars.cpp
index 201641e77a..3828cbdcd8 100644
--- a/toolkit/components/telemetry/tests/gtest/TestScalars.cpp
+++ b/toolkit/components/telemetry/tests/gtest/TestScalars.cpp
@@ -395,68 +395,6 @@ TEST_F(TelemetryTestFixture, ScalarEventSummary_Dynamic) {
                        scalarsSnapshot, 2);
 }
 
-TEST_F(TelemetryTestFixture, WrongScalarOperator) {
-  AutoJSContextWithGlobal cx(mCleanGlobal);
-
-  // Make sure we don't get scalars from other tests.
-  Unused << mTelemetry->ClearScalars();
-
-  const uint32_t expectedValue = 1172015;
-
-  Telemetry::ScalarSet(Telemetry::ScalarID::TELEMETRY_TEST_UNSIGNED_INT_KIND,
-                       expectedValue);
-  Telemetry::ScalarSet(Telemetry::ScalarID::TELEMETRY_TEST_STRING_KIND,
-                       NS_LITERAL_STRING_FROM_CSTRING(EXPECTED_STRING));
-  Telemetry::ScalarSet(Telemetry::ScalarID::TELEMETRY_TEST_BOOLEAN_KIND, true);
-
-  TelemetryScalar::DeserializationStarted();
-
-  Telemetry::ScalarAdd(Telemetry::ScalarID::TELEMETRY_TEST_STRING_KIND, 1447);
-  Telemetry::ScalarAdd(Telemetry::ScalarID::TELEMETRY_TEST_BOOLEAN_KIND, 1447);
-  Telemetry::ScalarSet(Telemetry::ScalarID::TELEMETRY_TEST_UNSIGNED_INT_KIND,
-                       true);
-  TelemetryScalar::ApplyPendingOperations();
-
-  JS::Rooted<JS::Value> scalarsSnapshot(cx.GetJSContext());
-  GetScalarsSnapshot(false, cx.GetJSContext(), &scalarsSnapshot);
-  CheckStringScalar("telemetry.test.string_kind", cx.GetJSContext(),
-                    scalarsSnapshot, EXPECTED_STRING);
-  CheckBoolScalar("telemetry.test.boolean_kind", cx.GetJSContext(),
-                  scalarsSnapshot, true);
-  CheckUintScalar("telemetry.test.unsigned_int_kind", cx.GetJSContext(),
-                  scalarsSnapshot, expectedValue);
-}
-
-TEST_F(TelemetryTestFixture, WrongKeyedScalarOperator) {
-  AutoJSContextWithGlobal cx(mCleanGlobal);
-
-  // Make sure we don't get scalars from other tests.
-  Unused << mTelemetry->ClearScalars();
-
-  const uint32_t kExpectedUint = 1172017;
-
-  Telemetry::ScalarSet(Telemetry::ScalarID::TELEMETRY_TEST_KEYED_UNSIGNED_INT,
-                       u"key1"_ns, kExpectedUint);
-  Telemetry::ScalarSet(Telemetry::ScalarID::TELEMETRY_TEST_KEYED_BOOLEAN_KIND,
-                       u"key2"_ns, true);
-
-  TelemetryScalar::DeserializationStarted();
-
-  Telemetry::ScalarSet(Telemetry::ScalarID::TELEMETRY_TEST_KEYED_UNSIGNED_INT,
-                       u"key1"_ns, false);
-  Telemetry::ScalarSet(Telemetry::ScalarID::TELEMETRY_TEST_KEYED_BOOLEAN_KIND,
-                       u"key2"_ns, static_cast<uint32_t>(13));
-
-  TelemetryScalar::ApplyPendingOperations();
-
-  JS::Rooted<JS::Value> scalarsSnapshot(cx.GetJSContext());
-  GetScalarsSnapshot(true, cx.GetJSContext(), &scalarsSnapshot);
-  CheckKeyedUintScalar("telemetry.test.keyed_unsigned_int", "key1",
-                       cx.GetJSContext(), scalarsSnapshot, kExpectedUint);
-  CheckKeyedBoolScalar("telemetry.test.keyed_boolean_kind", "key2",
-                       cx.GetJSContext(), scalarsSnapshot, true);
-}
-
 TEST_F(TelemetryTestFixture, TestKeyedScalarAllowedKeys) {
   AutoJSContextWithGlobal cx(mCleanGlobal);
   // Make sure we don't get scalars from other tests.
diff --git a/toolkit/components/telemetry/tests/python/test_histogramtools_strict.py b/toolkit/components/telemetry/tests/python/test_histogramtools_strict.py
index 2109cd7d35..28d4646dfd 100644
--- a/toolkit/components/telemetry/tests/python/test_histogramtools_strict.py
+++ b/toolkit/components/telemetry/tests/python/test_histogramtools_strict.py
@@ -485,53 +485,6 @@ class TestParser(unittest.TestCase):
         )
         self.assertRaises(SystemExit, ParserError.exit_func)
 
-    def test_gv_streaming_unsupported_kind(self):
-        SAMPLE_HISTOGRAM = {
-            "TEST_HISTOGRAM_GV_STREAMING": {
-                "record_in_processes": ["main", "content"],
-                "alert_emails": ["team@mozilla.xyz"],
-                "bug_numbers": [1383793],
-                "expires_in_version": "never",
-                "kind": "boolean",
-                "description": "Test histogram",
-                "products": ["geckoview_streaming"],
-            }
-        }
-        histograms = load_histogram(SAMPLE_HISTOGRAM)
-        parse_histograms.load_allowlist()
-        parse_histograms.Histogram(
-            "TEST_HISTOGRAM_GV_STREAMING",
-            histograms["TEST_HISTOGRAM_GV_STREAMING"],
-            strict_type_checks=True,
-        )
-        self.assertRaises(SystemExit, ParserError.exit_func)
-
-    def test_gv_streaming_keyed(self):
-        SAMPLE_HISTOGRAM = {
-            "TEST_HISTOGRAM_GV_STREAMING": {
-                "record_in_processes": ["main", "content"],
-                "alert_emails": ["team@mozilla.xyz"],
-                "bug_numbers": [1383793],
-                "expires_in_version": "never",
-                "kind": "exponential",
-                "low": 1024,
-                "high": 2**64,
-                "n_buckets": 100,
-                "keyed": "true",
-                "description": "Test histogram",
-                "products": ["geckoview_streaming"],
-            }
-        }
-        histograms = load_histogram(SAMPLE_HISTOGRAM)
-        parse_histograms.load_allowlist()
-        parse_histograms.Histogram(
-            "TEST_HISTOGRAM_GV_STREAMING",
-            histograms["TEST_HISTOGRAM_GV_STREAMING"],
-            strict_type_checks=True,
-        )
-
-        self.assertRaises(SystemExit, ParserError.exit_func)
-
     def test_enumerated_histogram_with_100_buckets(self):
         SAMPLE_HISTOGRAM = {
             "TEST_100_BUCKETS_HISTOGRAM": {
diff --git a/toolkit/components/telemetry/tests/python/test_parse_events.py b/toolkit/components/telemetry/tests/python/test_parse_events.py
index 0b7b91efcc..d6c7859eee 100644
--- a/toolkit/components/telemetry/tests/python/test_parse_events.py
+++ b/toolkit/components/telemetry/tests/python/test_parse_events.py
@@ -145,22 +145,6 @@ expiry_version: never
             ),
         )
 
-    def test_geckoview_streaming_product(self):
-        SAMPLE_EVENT = """
-methods: ["method1", "method2"]
-objects: ["object1", "object2"]
-bug_numbers: [12345]
-notification_emails: ["test01@mozilla.com", "test02@mozilla.com"]
-record_in_processes: ["content"]
-description: This is a test entry for Telemetry.
-products: ["geckoview_streaming"]
-expiry_version: never
-"""
-        event = load_event(SAMPLE_EVENT)
-        parse_events.EventData("CATEGORY", "test_event", event, strict_type_checks=True)
-
-        self.assertRaises(SystemExit, ParserError.exit_func)
-
 
 if __name__ == "__main__":
     mozunit.main()
diff --git a/toolkit/components/telemetry/tests/python/test_parse_scalars.py b/toolkit/components/telemetry/tests/python/test_parse_scalars.py
index c699cdb4d8..315c920a4a 100644
--- a/toolkit/components/telemetry/tests/python/test_parse_scalars.py
+++ b/toolkit/components/telemetry/tests/python/test_parse_scalars.py
@@ -243,25 +243,6 @@ bug_numbers:
         parse_scalars.ScalarType("CATEGORY", "PROVE", scalar, strict_type_checks=True)
         self.assertRaises(SystemExit, ParserError.exit_func)
 
-    def test_gv_streaming_keyed(self):
-        SAMPLE_SCALAR = """
-description: A nice one-line description.
-expires: never
-record_in_processes:
-  - 'main'
-kind: uint
-notification_emails:
-  - test01@mozilla.com
-products: ['geckoview_streaming']
-keyed: true
-bug_numbers:
-  - 12345
-"""
-
-        scalar = load_scalar(SAMPLE_SCALAR)
-        parse_scalars.ScalarType("CATEGORY", "PROVE", scalar, strict_type_checks=True)
-        self.assertRaises(SystemExit, ParserError.exit_func)
-
 
 if __name__ == "__main__":
     mozunit.main()
diff --git a/toolkit/components/telemetry/tests/unit/TelemetryEnvironmentTesting.sys.mjs b/toolkit/components/telemetry/tests/unit/TelemetryEnvironmentTesting.sys.mjs
index 0df6dfc2c1..1a4015df36 100644
--- a/toolkit/components/telemetry/tests/unit/TelemetryEnvironmentTesting.sys.mjs
+++ b/toolkit/components/telemetry/tests/unit/TelemetryEnvironmentTesting.sys.mjs
@@ -40,6 +40,8 @@ const PROFILE_RESET_DATE_MS = Date.now();
 // The profile creation date, in milliseconds (Yesterday).
 const PROFILE_FIRST_USE_MS = PROFILE_RESET_DATE_MS - MILLISECONDS_PER_DAY;
 const PROFILE_CREATION_DATE_MS = PROFILE_FIRST_USE_MS - MILLISECONDS_PER_DAY;
+const PROFILE_RECOVERED_FROM_BACKUP =
+  PROFILE_RESET_DATE_MS - MILLISECONDS_PER_HOUR;
 
 const GFX_VENDOR_ID = "0xabcd";
 const GFX_DEVICE_ID = "0x1234";
@@ -126,6 +128,7 @@ export var TelemetryEnvironmentTesting = {
         created: PROFILE_CREATION_DATE_MS,
         reset: PROFILE_RESET_DATE_MS,
         firstUse: PROFILE_FIRST_USE_MS,
+        recoveredFromBackup: PROFILE_RECOVERED_FROM_BACKUP,
       }
     );
   },
@@ -392,6 +395,10 @@ export var TelemetryEnvironmentTesting = {
       data.profile.firstUseDate,
       truncateToDays(PROFILE_FIRST_USE_MS)
     );
+    lazy.Assert.equal(
+      data.profile.recoveredFromBackup,
+      truncateToDays(PROFILE_RECOVERED_FROM_BACKUP)
+    );
   },
 
   checkPartnerSection(data, isInitial) {
diff --git a/toolkit/components/telemetry/tests/unit/test_TelemetryEnvironment.js b/toolkit/components/telemetry/tests/unit/test_TelemetryEnvironment.js
index 9990d83fdf..ca43772a07 100644
--- a/toolkit/components/telemetry/tests/unit/test_TelemetryEnvironment.js
+++ b/toolkit/components/telemetry/tests/unit/test_TelemetryEnvironment.js
@@ -712,6 +712,64 @@ add_task(async function test_addons() {
   await addon.uninstall();
 });
 
+add_task(async function test_signedTheme() {
+  AddonTestUtils.useRealCertChecks = true;
+
+  const { PKCS7_WITH_SHA1, COSE_WITH_SHA256 } = Ci.nsIAppSignatureInfo;
+
+  const ADDON_THEME_INSTALL_URL = gDataRoot + "webext-implicit-id.xpi";
+  const ADDON_THEME_ID = "{46607a7b-1b2a-40ce-9afe-91cda52c46a6}";
+
+  // Install the theme.
+  let deferred = Promise.withResolvers();
+  TelemetryEnvironment.registerChangeListener(
+    "test_signedAddon",
+    deferred.resolve
+  );
+  let theme = await installXPIFromURL(ADDON_THEME_INSTALL_URL);
+  await theme.enable();
+  ok(theme.isActive, "Theme should be active");
+
+  // Install an extension to force the telemetry environment to be
+  // updated (currently theme add-ons changes do not seem to be
+  // notified as changes, see EnvironmentAddonBuilder _updateAddons
+  // method for how changes to the environment.addons property are
+  // being detected).
+  const ADDON_INSTALL_URL = gDataRoot + "amosigned.xpi";
+  let addon = await installXPIFromURL(ADDON_INSTALL_URL);
+
+  await deferred.promise;
+  TelemetryEnvironment.unregisterChangeListener("test_signedAddon");
+
+  let data = TelemetryEnvironment.currentEnvironment;
+  TelemetryEnvironmentTesting.checkEnvironmentData(data);
+
+  // Check signedState and signedTypes on active theme data
+  // (NOTE: other properties of active theme are technically
+  // not covered by any other test task in this xpcshell test).
+  Assert.equal(
+    data.addons.theme.id,
+    ADDON_THEME_ID,
+    "Theme should be in the environment."
+  );
+  Assert.equal(
+    data.addons.theme.signedState,
+    AddonManager.SIGNEDSTATE_SIGNED,
+    "Got expected signedState on activeTheme"
+  );
+  Assert.equal(
+    data.addons.theme.signedTypes,
+    JSON.stringify([COSE_WITH_SHA256, PKCS7_WITH_SHA1]),
+    "Got expected signedTypes on activeTheme"
+  );
+
+  AddonTestUtils.useRealCertChecks = false;
+  await addon.startupPromise;
+  await addon.uninstall();
+  await theme.startupPromise;
+  await theme.uninstall();
+});
+
 add_task(async function test_signedAddon() {
   AddonTestUtils.useRealCertChecks = true;
 
diff --git a/toolkit/components/telemetry/tests/unit/xpcshell.toml b/toolkit/components/telemetry/tests/unit/xpcshell.toml
index 0c660888ed..ea5f6f418c 100644
--- a/toolkit/components/telemetry/tests/unit/xpcshell.toml
+++ b/toolkit/components/telemetry/tests/unit/xpcshell.toml
@@ -18,6 +18,7 @@ support-files = [
   "testNoPDBAArch64.dll",
   "!/toolkit/mozapps/extensions/test/xpcshell/head_addons.js",
   "../../../../mozapps/extensions/test/xpinstall/amosigned.xpi",
+  "../../../../mozapps/extensions/test/xpcshell/data/webext-implicit-id.xpi",
 ]
 generated-files = [
   "system.xpi",