Moved OWncloud: shared folders not in "shared" folder

Hello,

I had to move a owncloud 10.5 server (opensuse Tumbleweed) to a new machine (debian buster).
On buster only 10.8 was available, so I updated the server on the opensuse machine to 10.8, exported the DB, moved the “data”-Folder to the new machine, imported the DB and the config, run “occ upgrade” and everything seems to be fine.

Now the users tell me, that files and folders, which are shared with them, are no more under the “Shared” directory, but directly in the top folder.

Any clue why?

Regards

Daniel

Short comment:
config.php says: “‘share_folder’ => ‘/Shared’,”

But all files shared with me are directly under “/”
Also strange: new users have the shared files still under “/Shared”. Only existing users have it on /.