I ran ccleaner a while ago, so I don’t know if that’s the cause.
Anyway, Firefox is doing the following:
Not warning me when I close multiple tabs despite the box for that being checked
Occasionally failing to show a cursor in boxes (e.g., Google, Youtube) and also in the address bar, not allowing me to click there or modify or add text there.
Not remembering my computer has been there before when I log into online banking
Not automatically logging me into SDMB when I open it in a tab after opening a new Firefox session
MSE and Malware Bytes quick scans come up clean. Re-installing Firefox didn’t help.
Sometimes when Firefox starts behaving oddly it can be because of a corrupt Profile. The solution in this case is to uninstall, making sure you select to delete preferences, and then do a clean install.