Hey there,
I’m using Anki on my MacBook Pro and since today the desktop app crashes as soon as I try to select several cards in the “card administration” (unfortunately I don’t know the correct english description of this area as I’m using Anki in German). Already tried deinstalling the app and completely restarting my MacBook. Would really appreciate any further tips. Thx!
https://faqs.ankiweb.net/when-problems-occur.html
Especially check your installed add-ons.
Another thing you can try: after opening Anki, please try resetting the window positions in the preferences screen.