Deleting the last photo with a certain tag doesn't remove that tag from the active filter, can lead to crash

1. Run in debug mode (outside the debug mode, maybe some null reference happens silently here?)
2. Open a project with one photo, with the "A" tag.
3. Set Tag filter to "A".
4. Delete the photo using the thumbnail button. Mildly unexpectedly, after the photo (and the last instance of the tag) is deleted, the filter stays set to "A".
5. Click "Clear" next to tag filter. The application crashes.

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Alternatively, steps 1--4 as above, then

5b. Mouse over the Tag filter to open the filter panel, and uncheck "A". The application crashes.