1807687 - Focus rings randomly displayed on all links until firefox is restarted

Status: RESOLVED FIXED

(Core :: DOM: UI Events & Focus Handling, defect, P3)

Description

[Hitsin Vimpula]

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:107.0) Gecko/20100101 Firefox/107.0

Steps to reproduce:

Since around a few versions ago, after running firefox for a random period of time

Actual results:

Focus rings start to appear on all clicked links even though they are turned off in about:config

Expected results:

Focus rings are not displayed

Comment 1

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

The Bugbug bot thinks this bug should belong to the 'Core::DOM: UI Events & Focus Handling' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 2

[Emilio Cobos Álvarez (:emilio)]

What pref are you using to turn them off?

Comment 3

[Hitsin Vimpula]

browser.display.show_focus_rings and browser.display.focus_ring_on_anything are both in their default state (false).

Comment 4

[Emilio Cobos Álvarez (:emilio)]

Attachment: WIP: Bug 1807687 - WIP - Make Windows WM_UPPDATEUISTATE handling less error prone.

Comment 5

[Emilio Cobos Álvarez (:emilio)]

Attachment: Bug 1807687 - Simplify Windows keyboard indicator setting handling. r=cmartin,NeilDeakin

The only thing that can explain this is the WM_UPDATEUISTATE state
getting out of sync in a way that we think we need to unconditionally
show focus indicators for a window.

I tried to first make this less error prone (see patch above) but
digging more into these messages, I'm pretty sure we just don't need all
this code. See:

• https://devblogs.microsoft.com/oldnewthing/20130516-00/?p=4343
• https://devblogs.microsoft.com/oldnewthing/20130517-00/?p=4323

In particular, this is intended to be a windows feature to not show
keyboard indicators on dialogs until you use the keyboard. But that's
how Gecko dialogs behave already due to how :focus-visible behaves as
per:

https://searchfox.org/mozilla-central/rev/43ee5e789b079e94837a21336e9ce2420658fd19/toolkit/components/prompts/src/CommonDialog.jsm#319

I haven't been able to repro this state, but sounds believable that it
could happen after opening a native dialog or so on?

Instead of trying to fix this and untested code, let's just remove it. I
don't think it has any meaningful behavior difference as per the above,
and I also confirmed that other browsers don't handle this message.

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/7aa3f87292c6
Simplify Windows keyboard indicator setting handling. r=NeilDeakin

Comment 7

[Serban Stanca [:SerbanS]]

https://hg.mozilla.org/mozilla-central/rev/7aa3f87292c6