1907513 - Animated gif freezes when you're not interacting with page, with `transform-style:preserve-3d;` and `transform:translate3d(0,0,0);` on ancestors

Status: NEW

(Core :: Web Painting, defect)

Description

[kompa3]

Steps to reproduce:

I have a normal WordPress site with FooGallery that shows an animated gif.

Actual results:

The animated gif freezes randomly. Sometimes scrolling the page helps to gif to continue animation, but when mouse button is released the animation stops. Sometimes moving mouse cursor around makes the gif to animate a few moments before stopping again.

Expected results:

The gif should animate itself properly all the time like it does with Chrome and Edge.

Attached please find a screencast (in gif format) showing how the animated gif works with Chrome and then the problems that Firefox has.

The page is accessible at https://taskey.co.uk/ and the issue can be reproduced easily by opening it with Firefox and comparing it to how Chrome shows the animated gif of the front page.

Note that if the animated gif file is opened separately on a tab it shows properly with Firefox. So maybe Firefox somehow mistakenly interprets that the gif is not in the active scrolled content that is shown to the user and that's why the animation freezes?

Comment 1

[kompa3]

Attachment: Screencast (AVI) for first Chrome and then Firefox showing the animated gif

Comment 2

[kompa3]

Attached the screencast in zipped AVI format because the original screencast exceeded 10MB limit of Bugzilla attachments.

Comment 3

[Alice0775 White]

Attachment: reduced.zip

Comment 4

[Alice0775 White]

Regression window:
https://hg.mozilla.org/integration/mozilla-inbound/pushloghtml?fromchange=cfdb7af3af2e92e95f71ca2f1672bf5433beeb89&tochange=f56deec592bd3cff3e7f9eacb4786a3e50626fca

Comment 5

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

Set release status flags based on info from the regressing bug 1284350

:tnikkel, since you are the author of the regressor, bug 1284350, could you take a look? Also, could you set the severity field?

For more information, please visit BugBot documentation.

Comment 6

[Daniel Holbert [:dholbert]]

Attachment: (sample animated GIF for use in testcase)

Here's an animated GIF for use in my upcoming testcase. This is the image that we've got in-tree at https://searchfox.org/mozilla-central/source/image/test/browser/animated.gif

Comment 7

[Daniel Holbert [:dholbert]]

Attachment: reduced testcase 2