Show tile as empty if not defined

**Is your feature request related to a problem? Please describe.**

Undefined tiles are always shown with entity_id, icon etc. even if tile was never defined.
The information shown is always the one from the last defined tile selected.

Click tile 1 (defined) and then e.g. tile 30 (undefined) and both will look exactly the same.

**Describe the solution you'd like**

Show undefined tiles as empty.

**Describe alternatives you've considered, if any**

**Additional context**