2068886 - Firefox freezes completely when visiting a certain website

Status: RESOLVED DUPLICATE of bug 2068836

(Core :: Graphics: WebRender, defect)

Description

[Sören Hentzschel]

Firefox freezes completely when visiting a certain website. Firefox up to and including version 154.0.1 is not affected. Firefox 155 and the current Firefox Nightly freeze immediately.

STR:

1. open https://www.cls-design.com/test/

Actual:

Firefox freezes completely, and you have to force quit it, as Firefox becomes completely unusable.

Expected:

No freeze, you can still use Firefox.

Comment 1

[Sören Hentzschel]

I updated the URL because the original URL no longer reproduces the issue. A new test page has been created for this purpose.

Comment 2

[Dave Townsend [:mossop]]

Attachment: Spindump.txt

I see the GPU process using 100% CPU and the attached spindump suggests an infinite recursion in webrender::surface::order_readers_after

Comment 3

[Dave Townsend [:mossop]]

When accessing the page I see the GPU process using 100% of a CPU.

Comment 4

[Ryan VanderMeulen [:RyanVM]]

Narrowed down to https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=be36ed55e648665f0098388d4b1a07e94da92a18&tochange=64b39571ed7930978455ebbfbc5a3a6796ea0997 with mozregression

Comment 5

[Ryan VanderMeulen [:RyanVM]]

1:44.87 INFO: Last good revision: c71a05740ad516dd46480079e8afeba8a650504c
1:44.87 INFO: First bad revision: 4a03614ba69d89184d3e96fa06106a559ef3095e
1:44.87 INFO: Pushlog:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=c71a05740ad516dd46480079e8afeba8a650504c&tochange=4a03614ba69d89184d3e96fa06106a559ef3095e

Comment 6

[BugBot [:suhaib / :marco]]

:gw, since you are the author of the regressor, bug 2011747, could you take a look? Also, could you set the severity field?

For more information, please visit BugBot documentation.

Comment 7

[Ryan VanderMeulen [:RyanVM]]

The regressing change has been backed out from Beta for 156.0b3 and Release for 155.0.1.

Comment 9

[Alex Cornestean]

Since the regressing change has been backed out, I checked if the issue is still reproducible using the particular STR from Comment 0. I wanted to ensure the backout successfully fixed this specific variation (which differs slightly from the STR in Bug 2068836).

Testing on Windows 11 and Ubuntu 25.10, the issue no longer reproduces on the Release 155.0.1 candidate (155.0.1/20260903215306).

As Beta 156.0b3 is not yet available, I will follow up once the build is released.

I’ve also tested the latest Nightly (157.0a1/20260903215730). The issue is still reproducible there, as expected.