Sketchup crashes once I close a file

I use SU pro 2020 (Version 20.2.171). I usually work with two to three independent files at the same time. Once I choose to close one of the files, SU crashes immediately. Message received on screen: Crash #180030. Thanks for the autosave, I only need to reopen the app and start again, but it is frustrating when this keeps happening each time I close a file.
I use few extensions. May be one of them causes a conflict of some kind. Who knows.
Could anybody guess the reason for this crash?
Has anybody experienced the same?
Thank you in advance for for your help. Much appreciated.