I was getting an unspecified bug with Mozilla VPN that wouldn't let me launch it, update it, or sign out of it. I decided to uninstall and reinstall it. Uninstalling the VPN required me to close out of Firefox. I did so. When I relaunched it after the uninstall so I could go download the new VPN files, Firefox was still displaying the tab titles but nothing else, not even the urls of the pages. The entire browser was completely blank except for the tabs. No other pages are accessible either. I tried restarting the computer. It didn't work. I tried uninstalling Firefox, restarting the computer, and reinstalling Firefox. It didn't work. I tried a clean reinstall where I deleted every scrap of leftover data I could find. It didn't work. I got a VCRUNTIME140_1.DLL error during an install attempt, which I attempted to fix by updating Visual Studio as outlined here https://support.mozilla.org/en-US/questions/1352013 and that didn't fix it either.