Closed Bug 1466992 Opened 6 years ago Closed 4 years ago

Menu items are poorly rendered when scrolling.


(Firefox for Android Graveyard :: General, enhancement, P5)

Firefox 62


(Performance Impact:none, fennec?, firefox62 affected)

Performance Impact none
Tracking Status
fennec ? ---
firefox62 --- affected


(Reporter: karlcow, Unassigned)


(Depends on 1 open bug, )


(Whiteboard: [webcompat])

1. Visit the site
2. Tap on the menu button
3. Scroll down the menu panel

When scrolled, the menu items behave badly as shown in the screenshot below.

This issue does not occur in Chrome 66, Android 7.0. However, this issue may spread out to more websites using Material Design Components for Web.
tracking-fennec: --- → ?
Hardware: Unspecified → All
This seems like grahic layers APZ issue not a perf issue.
Whiteboard: [webcompat] [qf] → [webcompat] [qf-]
(In reply to Karl Dubost :karlcow from comment #0)
> When scrolled, the menu items behave badly as shown in the screenshot below.

Specifically, the menu-items jitter / blink **while being scrolled**.

This feels APZ-ish -- kats/botond, would you mind taking a look at this from an APZ perspective?
It looks like this page is just continually repainting even when it appears idle. And the compositor side layer tree is constantly changing with respect to the number and arrangement of layers. I don't understand what's going on.

It does seem like an APZ issue, but it's going to be painful to debug.
Actually it might be that there's so much spew to logcat that it's dropping output, making it look like the layer tree is changing.

And the infinite painting happens on desktop as well, causing my laptop to get quite hot.
Filed bug 1469947 for the perf implications, which we can keep separate from the visual glitching on Android. However, the visual glitching will be a lot easier to investigate if the painting isn't going full-throttle.
Depends on: 1469947
Re-triaging per

Needinfo :susheel if you think this bug should be re-triaged.
Priority: P3 → P5

Migrating Webcompat whiteboard priorities to project flags. See bug 1547409.

Webcompat Priority: --- → ?

See bug 1547409. Migrating whiteboard priority tags to program flags.

This looks fine on my phone, please reopen if this is still an issue.

Closed: 4 years ago
Resolution: --- → WORKSFORME
Product: Firefox for Android → Firefox for Android Graveyard
Performance Impact: --- → -
Whiteboard: [webcompat] [qf-] → [webcompat]
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