Hi, using Iobit software is a good way to keep doing it weekly.

Your Video Card Drivers for : adapterDescription: NVIDIA GeForce GTX 670 shows a error : featureLog: {u'fallbacks': [{u'message': u'Unsupported by driver', u'name': u'NO_CONSTANT_BUFFER_OFFSETTING'}

The rest of the information on your drivers is really good. It can cause issues as Firefox loves nice drivers so it can render what you want. https://support.mozilla.org/en-US/kb/upgrade-graphics-drivers-use-hardware-acceleration

Suggest backup and it will not be as bad a deal when it does happen :

• https://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer
• https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

Check Windows Event Viewer and see what went on at the time Firefox Refreshed, if any thing or if there is something there to figure out.

A clean install of all Firefox program files might be good : uninstall Firefox. Then Delete the Mozilla Firefox Folders in C:\Program Files , C:\Program Files(x86) & C:\ProgramData Then restart system. Then run Windows Disk Cleanup. (Note: This should be Pinned and run Weekly, If never done below expect 10's of gig's(WIn10) Then run it again and click the button that says Cleanup System Files. Note: your Firefox Profile is saved. Reinstall with Current Release Firefox 61.0.2 with a Full Version Installer

• https://www.mozilla.org/firefox/all/

Please let us know if this solved your issue or if need further assistance.

There was some kind or error with Windows Loading when this happened as Windows "failed to load" properly which I restarted the system. Also looking at my Firefox crash reports at around the same time there was a report on which the signature was IPCError-browser | ShutDownKill. I have no idea what that driver message means,as all my drivers are up-to-date as on this week. Also somehow looking at my Firefox Profiles folders I have no fewer than 4 profiles listed,if that's contributing to the problem.