Found in

• Firefox 107.0b4

Affected versions

• Firefox 107.0b4
• Firefox 108.0a1

Tested platforms

• Affected platforms: Windows 7
• Unaffected platforms: Ubuntu 18.4, macOS 10.12.6

Steps to reproduce

1. Launch Firefox with menu bar enabled
2. Enable any theme from about:addons
3. Enter full screen (F11)

Expected result

• Browser window controls are displayed twice in full screen when a theme is enabled

Actual result

• Browser window controls should be displayed only once with theme and menu bar enabled

Regression range

• Unlikely a recent regression, issue is reproducible with Fx 102
• Will search for a regression asap.

Additional notes

• Browser window controls are shown properly with menu bar and system theme enabled
• See the attached screenshot

I have investigated the issue in order to find a regression range, and it seems that Bug 1745189 is the regressor for this behavior:

• changeset: 71d227d9699cb1da297ddc25ca5bf08b5dcd8c3c
• pushlog_url: https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=71d227d9699cb1da297ddc25ca5bf08b5dcd8c3c&tochange=f007b3b66bb91d97049fb9ff31ab6cc6aab36fd8

:emilio, since you are the author of the regressor, bug 1745189, could you take a look?

For more information, please visit auto_nag documentation.

Set release status flags based on info from the regressing bug 1745189

https://hg.mozilla.org/mozilla-central/rev/1cd8b7e2b9b4

The patch landed in nightly and beta is affected.
:emilio, is this bug important enough to require an uplift?

• If yes, please nominate the patch for beta approval.
• If no, please set status-firefox108 to wontfix.

For more information, please visit auto_nag documentation.

Comment on attachment 9303508 [details]
Bug 1797280 - Fix windows 7 selectors to avoid overriding fullscreentoolbar rules. r=dao,Gijs

Beta/Release Uplift Approval Request

• User impact if declined: comment 0
• Is this code covered by automated tests?: No
• Has the fix been verified in Nightly?: Yes
• Needs manual test from QE?: Yes
• If yes, steps to reproduce: comment 0
• List of other uplifts needed: none
• Risk to taking this patch: Low
• Why is the change risky/not risky? (and alternatives if risky): Very simple CSS fix.
• String changes made/needed: none
• Is Android affected?: No

Verified as fixed on Windows 7 x64 on Firefox 109.0a1 (2022-11-17).

Comment on attachment 9303508 [details]
Bug 1797280 - Fix windows 7 selectors to avoid overriding fullscreentoolbar rules. r=dao,Gijs

Approved for 108.0b3

https://hg.mozilla.org/releases/mozilla-beta/rev/e0515cfb255b

Verified as fixed on Windows 7 x64 on Firefox 108.0b3.

Comment on attachment 9303508 [details]
Bug 1797280 - Fix windows 7 selectors to avoid overriding fullscreentoolbar rules. r=dao,Gijs

Approved for 102.6esr.

https://hg.mozilla.org/releases/mozilla-esr102/rev/067fcde761df

Verified as fixed on Windows 7 x64 on Firefox 102.6esr.