I would try stopping any virus software running and try starting in safe mode.

To start Firefox in Safe Mode:

   Click the menu button. , click Help and select Restart with Add-ons Disabled…. Firefox will start up with the Firefox Safe Mode dialog. ...
   When the Firefox Safe Mode window appears, click the Start in Safe Mode button.

Anything in the Windows Event log ?

where would I find it in the event log?

Try the Windows Event Viewer app. I think the easiest way to access it would be to use the Windows 10 system search box and enter event and then when you get Event Viewer on the results, click that to start the app. Some of the logs are huge, so they are slow to load. The one I suggest checking is

Windows Logs > Application

If you find a fresh entry referring to a problem with Firefox, you could copy paste the text details into a reply.

Faulting application name: firefox.exe, version: 84.0.1.7660, time stamp: 0x5fe0d17b Faulting module name: gemmauf64.dll, version: 1.27.100.0, time stamp: 0x5f5a3902 Exception code: 0xc0000005 Fault offset: 0x0000000000026763 Faulting process id: 0x5740 Faulting application start time: 0x01d6dd178d2d49fd Faulting application path: C:\Program Files\Mozilla Firefox\firefox.exe Faulting module path: C:\Program Files\Bitdefender\Bitdefender Security\gemmauf\264891123445032704\gemmauf64.dll Report Id: 86306353-f751-4d64-93b9-45cfacae2519 Faulting package full name: Faulting package-relative application ID:

does this help?

Faulting application name: firefox.exe, version: 84.0.1.7660, time stamp: 0x5fe0d17b Faulting module name: gemmauf64.dll, version: 1.27.100.0, time stamp: 0x5f5a3902 Exception code: 0xc0000005 Fault offset: 0x0000000000026763 Faulting process id: 0x5740 Faulting application start time: 0x01d6dd178d2d49fd Faulting application path: C:\Program Files\Mozilla Firefox\firefox.exe Faulting module path: C:\Program Files\Bitdefender\Bitdefender Security\gemmauf\264891123445032704\gemmauf64.dll Report Id: 86306353-f751-4d64-93b9-45cfacae2519 Faulting package full name: Faulting package-relative application ID:

it's not letting me post the thing, why

Sorry, something in the data looks like a URL or phone number. A moderator will need to approve it.

ah, do I have to request approval orrr?

No, there's a "suspected spam" queue that the moderators check many times a day.

ah, I'll just wait I guess

Your reply contains numbers that the anti-spam filter that is used interprets as possible spam.

When you post a reply that that triggers anti spam measures like an external link or special numbers then this reply needs to be examined and approved by a moderator as an anti-spam feature, so there can be a delay before your reply appears.

This looks like a problem with Bitdefender, so maybe contact them for support.

• Faulting module path: C:\Program Files\Bitdefender\Bitdefender Security\gemmauf\264891123445032704\gemmauf64.dll

will do then, thanks a ton