I forgot to mention but I'm using Windows 11 Home version 10.0.26100. Other browsers such as google chrome and edge are functioning just fine.

Firefox 140 for Windows has a bug that renders it vulnerable to crashing instantly on startup in the presence of certain third-party DLLs.

A 140.0.1 update is planned to fix the bug, but I don't know the schedule for release. In the meantime, hopefully you can get by with Chrome or Edge.

Thank you for the information. I should be fine until the update arrives.

Firefox 140.0.1 is out, so you can test whether it helps and let us know here or add to a thread on Reddit:

• Release notes: https://www.mozilla.org/firefox/140.0.1/releasenotes/
• To download an installer: https://www.mozilla.org/firefox/all/desktop-release/
• Feedback thread: https://old.reddit.com/r/firefox/comments/1ll0rps/firefox_14001_released_with_hopefully_fix_to/

Alternately, some affected users have worked around the issue by renaming firefox.exe to something different, such as firefox1.exe. If you wanted to try that, the file is usually here:

C:\Program Files\Mozilla Firefox\firefox.exe

Renaming the file will break your normal shortcut, but after renaming, you can create a new shortcut:

• Windows 10: right-click firefox1.exe > Send to > Desktop (create shortcut)
• Windows 11: right-click firefox1.exe > Show more options > Send to > Desktop (create shortcut)

(The next update will create a new firefox.exe in the folder, so you'll need to remember to delete firefox.1.exe and its shortcut after that.)