1962641 - Automatically unloaded tabs due to low memory have faded favicons despite not being explicitly unloaded

Status: RESOLVED FIXED

(Firefox :: Tabbed Browser, defect)

Description

[Kestrel]

STR:

1. Make sure the following settings are applied:
   browser.tabs.fadeOutExplicitlyUnloadedTabs = true
browser.tabs.fadeOutUnloadedTabs = false
browser.tabs.unloadOnLowMemory = true
2. Force a low memory condition by changing browser.low_commit_space_threshold_percent = 100.
3. Open many tabs and wait for them to automatically unload or visit about:unloads and click the "Unload" button.

Expected:
Only tabs explicitly unloaded by right-clicking and choosing "Unload Tab" have faded favicons.

Actual:
Automatically unloaded tabs have faded favicons even though browser.tabs.fadeOutUnloadedTabs is false and they were not explicitly unloaded by the user.

Regression window:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=3a5a672cbf434cde59ddeb10decbdf3bf4314bf1&tochange=2895d98e1d2b4191040d42841f90961dd76c0eca

Regressed by Bug 1926973.

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

Set release status flags based on info from the regressing bug 1926973

:gstoll, since you are the author of the regressor, bug 1926973, could you take a look? Also, could you set the severity field?

For more information, please visit BugBot documentation.

Comment 2

[Greg Stoll :gstoll]

Hopefully we can just set some sort of different class on the tab when it's unloaded explicitly and use that selector in the CSS.

Comment 3

[Greg Stoll :gstoll]

Attachment: Bug 1962641 - only style explicitly unloaded tabs with grayscale favicon, etc. r=#tabbrowser-reviewers!

Tabs can also be unloaded for low memory conditions, so only add the
"discarded" attribute if the tab was unloaded explicitly.

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/06bc5877698f
only style explicitly unloaded tabs with grayscale favicon, etc. r=tabbrowser-reviewers,dao

Comment 5

[Cosmin Sabou [:CosminS]]

https://hg.mozilla.org/mozilla-central/rev/06bc5877698f