Admin interface is basically broken on mobile devices

[lkiesow]

The admin interface is basically broken on mobile devices:

The biggest problem for this are the big tables. On smaller devices, we should replace them with or turn them into something else.

Another problem are the modal dialogs. Since they are problematic for a11y anyway, maybe we can get rid of them?

[Arnei]

Sounds like we need someone to create a good mobile design.