1981057 - Flickering on select opening

Status: UNCONFIRMED

(Core :: Graphics: WebRender, defect, P2)

Description

[bano.notit]

Attachment: Select flickering.mp4

Steps to reproduce:

1. Open https://camillovisini.com/coding/simulating-hand-drawn-motion-with-svg-filters#animating-the-effect
2. Scroll until star example
3. Tap on Image selector to change star to something else

Actual results:

The whole browser started flickering and became unresponsive. The shadow around select modal started thickening. Video attached.

Expected results:

It should just show the select modal.

Android 10, MUI 12, Redmi Note 8 Pro

Comment 1

[bano.notit]

Attachment: FF flickering desktop.mp4

Comment 2

[bano.notit]

Same problem can be reproduced on FF 141.0 (64-bit) Desktop. But it has less severity there.

Comment 3

[Titouan Thibaud [:titouan]]

I couldn't reproduce on Android devices (Android 15 and 16, Fx 143).

But if it can be reproduced on Desktop too, I guess this is related to Gecko. Moving to Graphics, I hope it's the right component.

Comment 4

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

The severity field is not set for this bug.
:bhood, could you have a look please?

For more information, please visit BugBot documentation.

Comment 5

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

The severity field is not set for this bug.
:bhood, could you have a look please?

For more information, please visit BugBot documentation.

Comment 6

[Bob Hood [:bhood]]

Ashley, SVG filter involvement?

Comment 7

[Ashley Hale [:ahale]]

SVG filter involvement - yes, but not WebRender as we don't currently accelerate feTurbulence or feDisplacementMap.

I'm not an expert on the blob fallback code, but maybe someone else knows what is going on here.

Comment 8

[Robert Longson [:longsonr]]

Really needs a reduced testcase. My guess at the moment is that the filter bounds (defaulting to 10% extra round the shape) overlap the select and cause it to repaint. If so this is really a site issue as the site should set the correct filter bounds.

Comment 9

[bano.notit]

Can I as an outsider try to make a reduced testcase? Is there any public doc that can help me with that?

Comment 10

[Timothy Nikkel (:tnikkel)]

You just take the page showing the bug and then remove things from the page while keeping the page showing the bug still until you can no longer remove anything and still show the bug.

Comment 11

[Robert Longson [:longsonr]]

Looks like webkit have a document: https://webkit.org/test-case-reduction/