You're on an old OS and old browser. I still have another laptop with win7 and see all the same issues. Here you can see many win7 user all having the same issues. https://support.mozilla.org/en-US/questions/firefox?tagged=windows-7&show=responded

Try the same steps on a newer computer and see what happens.

Thanks for the reply.

I'll switch to Windows 11.

Sounds like a plan. Mark this as resolved if you have no further questions and have a nice day.

With that Windows 7 system you could try to use a current Linux distro whether in replacing or by dual boot with Windows 7. This way you can use the current versions of Firefox with updates, more so if you use the tarball version from Mozilla and not package builds.