* Prevent adding nil label to .AddedLabels or .RemovedLabels
There are possibly a few old databases out there with malmigrated data that can
cause panics with empty labels being migrated.
This PR adds a few tests to prevent nil labels being added.
Fix#14466
Signed-off-by: Andrew Thornton <art27@cantab.net>
* Add doctor command to remove the broken label comments
Signed-off-by: Andrew Thornton <art27@cantab.net>
Co-authored-by: 6543 <6543@obermui.de>