The Digikam Tags View sometimes shows images that do not have the selected tag.

I have the following Tag Tree:
People
|
--Last Name
  |
  --First Name
Buildings
|
--Country
  |
  --City

When I select the "People" Tag, I expect that no images with a tag from the "Buildings" Tag tree are shown (except if they have a People tag ;).
However, I have a few images that have a single tag: "City" from the "Buildings" tree. When I select the People Tag, these images are shown as well. That should not happen.

Expected behaviour:
When I select a parent Tag, only images with the parent tag, or its children, are shown.