TextEdit - Crashes / Hang Event while using BigSir

There is no reason to ever install or run any 3rd party "cleaning", "optimizing", "speed-up", anti-virus, VPN or security apps on your Mac.  This user tip describes what you need to know and do in order to protect your Mac: Effective defenses against malware and other threats - Apple Community   

That being said uninstall Avira Security according to the developer's instructions.

Regarding Safe Mode: does TextEdit to crash whenever you use it or is it random? If you can make TextEdit to crash easily then try doing so in Safe Mode. Then reboot normally and try again. This is what Safe Mode does:

NOTE: Safe Mode boot can take up to 10 minutes as it's doing the following; 

• Verifies your startup disk and attempts to repair directory issues, if needed

• Loads only required kernel extensions (prevents 3rd party kernel/extensions from loading)

• Prevents Startup Items and Login Items from opening automatically

• Disables user-installed fonts 

• Deletes font caches, kernel cache, and other system cache files

Also log into another vanilla admin user account, Set up users, guests, and groups on Mac,  and see if the problem persists. (This tells us if the problem is limited to your user account or is system wide).