Desktop environments can be uninstalled...
Is there an optimal way to do it?
I tried apt remove task-desktop but I feel is going to remove too much stuff. especially python modules...
The openmediavault package is removed. You might be able to reinstall it but you have quite the mess. sudo apt-get install openmediavault Running the fix script won't hurt either.
I'll try, otherwise I'll restore from the backup.
With the fix script you mean omv-firstaid?