When switching between day grouping and week grouping in the work unit list, the work unit list displays empty groups and the filtering does not work properly.
Preconditions:
- Database contains a tag.
- Week 1: Has work units that are all tagged with the tag.
- Week 2: Has work units where only some are tagged with the tag.
- Week 3: Has work units where no units are tagged with the tag.
- Work unit list grouping is set to "By Day"
Steps to reproduce:
- On the work unit list, filter by the tag with "Inverse Filters" active.
- Only days with work units without this tag get displayed.
- Go to the settings, select grouping "By week".
- Go back to work unit list.
Observable behavior:
- Week 1: Category displayed, but does not contain any work units:

- Week 2: Category displayed, all work units displayed (Both work units with and without the tag)
- Week 3: Category correctly displayed.
Expected behavior:
- When going back to the list, the list should properly display filtered results.
Additional notes:
- It would be nice to be able to switch the grouping directly on the work unit list.
WorkingHours version: 2.6.11.0
OS + version: Windows 10