Adding upstream version 124.0.1.upstream/124.0.1

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

3 files changed, 58 insertions, 0 deletions

diff --git a/browser/components/tabunloader/docs/fullmode.png b/browser/components/tabunloader/docs/fullmode.png
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diff --git a/browser/components/tabunloader/docs/index.rst b/browser/components/tabunloader/docs/index.rst
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+Tab Unloading
+=============
+
+Tab Unloading is a feature that automatically unloads tabs to prevent Firefox
+from crashing due to insufficient memory when the system’s available memory is
+low.
+
+The feature consists of two parts: memory pressure detector and tab unloader.
+When the memory pressure detector detects a low memory situation, it triggers
+the tab unloader that prioritizes tabs and chooses a tab to unload, or if there
+are no unloadable tabs, triggers the internal memory-pressure warning allowing
+the browser’s subsystems to reduce their memory use.
+
+There are two modes to prioritize tabs.
+
+Firefox basically unloads tabs in least-recently-used order, excluding
+tabs playing media, using Picture-in-Picture, or using WebRTC.  Pinned
+tabs are deprioritized and are less likely to be unloaded.
+
+When there are more tabs opened, in most cases when there are more than
+eleven tabs, Firefox does extra calculations identifying processes hosting
+tabs and estimates memory usage of each tab, and then unloads tabs with
+larger memory and more processes that will be terminated by tab unloading.
+
+You may disable the feature by setting the preference
+``browser.tabs.unloadOnLowMemory`` to ``false``.
+
+about:unloads
+-------------
+
+The about:unloads page shows how Firefox prioritizes tabs and which tab will
+be unloaded when the tab unloader is triggered.  You can trigger tab unloading
+manually by clicking the **Unload** button in the page.
+
+The page contains a table where existing tabs are displayed in the same order
+used by Firefox to choose the next tab to unload.  When you click the button,
+a tab shown in the first row, which has the lowest value in the **Priority**,
+is unloaded.  If the value of **Priority** is a hyphen (-), the corresponding
+tab is not unloadable.
+
+In the first of the two modes mentioned above, Firefox calculates **Last Accessed**
+and **Base Weight** for each tab and orders tabs by those values, not calculating
+the other attributes such as **Secondary Weight** to save CPU power.  Below is
+an example of this case.
+
+.. image:: lightmode.png
+
+In the second mode, Firefox identifies processes hosting each tab and shows
+their process IDs in the **Process IDs** column.  Process IDs are displayed in
+**bold** when they are hosting the tab’s top frame, and in *italic* when the
+process is shared between different tabs.
+
+After identifying the processes of all tabs, Firefox estimates memory usage of
+tabs and calculates the secondary weight for tabs that are not recently accessed.
+For recently accessed tabs, Firefox does not calculate the **Secondary Weight**
+and **Memory**, leaving those columns empty.
+
+.. image:: fullmode.png
diff --git a/browser/components/tabunloader/docs/lightmode.png b/browser/components/tabunloader/docs/lightmode.png
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