Another Clue:
When I tried to calculate the used disk space for files, I gave myself permissions for "'System volume Information" folder. (For security reasons it can be only modified by system). After that, I removed my user name from the names, to get just the same state before the operation.
After that, the tab dissapeared. I dont know why, or what is the point, but I need to give the user read permissions for the folders to get the restore tab back.
If it's not problematic you can try this also.
Regards