Actually, in Ubuntu 18.04 and presumably 17.10, the day and time are displayed up top on the login screen. And you can click on it to show the calendar with the date. So it sounds like Kai is using some older Ubuntu release....
Kai, please run 'apport-collect 1733249' on the affected machine to help us understand what you're running. ** Changed in: gdm3 (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Desktop Bugs, which is subscribed to gdm3 in Ubuntu. https://bugs.launchpad.net/bugs/1733249 Title: No time displayed on lock screen. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gdm3/+bug/1733249/+subscriptions -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs