Closed Bug 1555543 Opened 5 months ago Closed 5 months ago

APZ-related scrollbar UA style sheet rule doesn't apply in shadow trees

Categories

(Core :: Layout, defect, P3)

defect

Tracking

()

RESOLVED FIXED
mozilla69
Tracking Status
firefox69 --- fixed

People

(Reporter: heycam, Assigned: heycam)

Details

Attachments

(1 file)

On Android we have this UA style sheet rule:

https://searchfox.org/mozilla-central/source/mobile/android/themes/geckoview/scrollbar-apz.css

It looks like that wants to match XUL <scrollbar> elements in HTML documents. It's not always the case that the root element is an <html> element (script can replace the root with any kind of element). But also this rule won't match for scrollable elements inside shadow trees, since we don't look up past the shadow root when selector matching.

Kats, am I right that the intention here is to limit this rule to scrollbars in HTML documents? Is there a need to do that, or can we just replace this selector with xul|scrollbar?

Flags: needinfo?(kats)

There used to be a xul|window xul|scollbar { display: block; } rule until bug 1223928 removed it.

I'll just upload a patch; let me know if I'm missing something.

Flags: needinfo?(kats)

Currently it won't match scrollbar elements in HTML documents where the
root element has been switched out for something other than <html>, or
in shadow trees.

Assignee: nobody → cam
Status: NEW → ASSIGNED
Pushed by cmccormack@mozilla.com:
https://hg.mozilla.org/integration/autoland/rev/66cee597c19d
Adjust scrollbar-apz.css rule so it applies to all scrollbar elements. r=kats
Status: ASSIGNED → RESOLVED
Closed: 5 months ago
Resolution: --- → FIXED
Target Milestone: --- → mozilla69
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