[Bug]: crash when you highlight too much text

[StrangeUser]

Pre-Submission Checklist

• [X] I have checked the existing/closed issues to ensure this issue has not already been reported.
• [X] I am using the latest supported version of the browser.
• [X] I have tried disabling all browser extensions/add-ons to rule out interference from these.
• [X] I have tried clearing the browser cache and cookies.
• [X] I have checked with a new profile and the issue still occurs.
• [X] I have provided detailed step-by-step instructions on how to reproduce the issue.
• [X] I have included relevant screenshots or console outputs.
• [ ] I have checked that this problem is not occurring in the latest version of Firefox ESR.
• [X] This issue is specific to this browser and does not occur in other browsers.

Bug Summary

Browser crashes when you highlight a lot of text.

Reproduction Steps

1. Enter github gist (or, probably, any other site, that does same function, pastebin, news sites, etc)
2. Begin highlighting text (approx 500 rows on gitgist)
3. Either stop holding mouse button or press RMB
4. Expect crash

Expected Behavior

I am able to stop highlighting text

Actual Behavior

In fact, i can't stop highlighting. I should either keep holding my mouse button or experience crash.

Screenshots

https://github.com/user-attachments/assets/8a09f73c-1679-442d-a565-7e5e50beefb3

Browser Version

11.20.0 (64-bit) | Firefox: 128.5.0

Operating System

Windows 11

Additional Context

This never happened to me in firefox, i been able to highlight as much text, as i want without crashing. Also, video above is done on clean profile, without any extensions and so on.