I am using Cryptomator with Google Drive in a shared folder with other user (that obviously is also using Cryptomator, in a different computer). I would like to know what happens if the other user edit files of that folder at the same time as me?
Editing a different file in the same directory will “just work”.
If you edit the exact same file, it depends on your synchronization tool. In case of Google Drive, it will detect concurrent modifications and create a conflict. The conflict is then recognized by Cryptomator, i.e. it will show you both versions of the file. One version with the normal name, the other one with
(conflict) appended to its name.
It’s dangerous if two people edit a file at the same time. The danger when multiple users are using the same files is that if two people edit a file at the same time, the file is guaranteed to be corrupted.
That is incorrect. It depends on a lot of parameters. Especially on the cloud service and sync software you use.
In general, the cloud will keep both versions of the file. Cryptomator is capable of recognizing this and showing both cleartext versions to the user.