I have LO7.1 in Windows 10. In Calc every time I try Print Preview, Full screen view or try to close Calc, it crashed the whole LO. I created a fresh user profile and it does happen also in safe mode. Only in Calc, all other apps run just fine.
More puzzling is that this does not happen on other two laptops I have also with Windows 10.
Also, LO7.0 it seems to be working fine on all three machines.
Has Windows been Restarted, Start menu > Power > Restart* (not Shut Down as the default for that is Hibernate)?
Is Windows Up to date? Start menu > Settings > Update and Security > Windows Update, are there any updates waiting to be installed or waiting for restart?
Given that it happens in Safe Mode, I would then be inclined to try repairing LibreOffice. Open Control Panel > Programs and Features, find LibreOffice 7.1, right-click on it and select Repair. Cheers, Al