Firefox can remain stuck while loading pages under high load

[kyouhei-horizumi]

Environment

• Firefox: 155.0.1
• NoScript: 13.6.32
• OS: Windows 11

Steps to reproduce

1. Enable NoScript.
2. Repeatedly create tabs using browser.tabs.create().
3. Continue doing so under high load.
4. Eventually, one of the newly created tabs may remain stuck while loading.

I have not yet found a 100% reliable minimal reproduction, but I can reproduce the problem under sustained tab creation / page loading.

Actual behavior

One tab becomes stuck while loading and does not recover.

After the problem occurs:

• the affected tab remains stuck indefinitely;
• waiting several additional minutes does not make it recover;
• other similar requests/tabs may still complete normally;
• in some cases, page loading in other tabs is also affected;
• disabling NoScript or restarting Firefox restores normal loading.

In my latest test, I left the affected tab in this state for more than 4 additional minutes, but it still did not complete.