1955077 - Firefox freezes and cause Windows hang when access certain websites

Status: UNCONFIRMED

(Core :: Performance: General, defect)

Description

[Hantong Chen]

Attachment: about_support.txt

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:136.0) Gecko/20100101 Firefox/136.0

Steps to reproduce:

In recent major versions, it has been observed that when accessing certain websites, Firefox suddenly freezes, and the system is also affected. Symptoms include extremely slow or completely unresponsive mouse movements, the taskbar clock stopping updates, and more severely, the system will completely stop responding (though audio may still output normally unless random operations during system unresponsiveness cause complete lockup), including Ctrl + Alt + Del.

However, this issue is self-limiting - after waiting about a minute, the system regains responsiveness and displays a dialog prompting to forcefully terminate Firefox. After terminating the process, everything returns to normal.

I found a website that I can consistently reproduce the issue on my local machine when I access. I have posted online to ask other users - some reported being able to reproduce it, while others couldn't. According to the post replies, it seems that only Windows 11 24H2 users will suffer from this issue. The post is here (in Chinese).

I have seached the familiar issues and tried the following, though none of them helps:

• Any under https://support.mozilla.org/en-US/kb/firefox-hangs-or-not-responding
• Run Firefox in troubleshoot mode
• about:crashes reports nothing. The same as WER but simple message The program firefox.exe version 136.0.2.571 stopped interacting with Windows and was closed. To see if more information about the problem is available, check the problem history in the Security and Maintenance control panel.

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Info that may helps:

• System version:

  Edition: Windows 11 Pro for Workstations
  Version: 24H2
  OS build: 26100.3194
  Experience: Windows Feature Experience Pack 1000.26100.48.0

• Graphic card and driver version:

  • NVIDIA GeForce RTX 4060 Laptop GPU, 32.0.15.7247
  • AMD Radeon(TM) 890M Graphics, 32.0.12033.1030

• Firefox version: 136.0.2.571

• about:support: attached

Actual results:

Firefox and system hang.

Expected results:

The system should not hang but allow me to forcefully terminate Firefox.

Comment 1

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

The Bugbug bot thinks this bug should belong to the 'Core::Performance' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 2

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

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

For more information, please visit BugBot documentation.

Comment 3

[Bas Schouten (:bas.schouten)]

After numerous people trying, we have sadly still been unable to reproduce this issue. In the meanwhile, any additional information would be much appreciated.

Could you also verify whether this issue reproduces without extensions installed? (I.e. when using safemode)

Comment 4

[Hantong Chen]

This issue can be reproduced without extensions installed (i.e. when using safemode).

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Add:

This issue may be more related to Windows 11 24H2, as I could also reproduce it with Chromium 136 (though didn't completely freeze the system like Firefox 136). Firefox 137 seems to partially fix this issue (will not completely freeze the system and recover in less than a minute).

One possible reproduction condition is that the system keeps running without being shutted down for about three to four days.