"Catalog Filter" pane, exclude category dysfunctional?

[nji9]

If I choose a category to use as filter, the appropriate images are shown.

But if I choose a category to use as exclude filter (Alt-left mouse)
the icon in the pane changes,
but the results doesn't filter for images not assigned to the category.
There has to be another category chosen as filter (but not "All"),
to make the exclusion of a sub category work.

In other words:
The exclude filter for a category seems to work (icon change), but doesn't.

I know I can identify the images that are not assigned to a category
by the find function (quite cumbersome), but why doesn't it do at
Catalog filter pane?

Is it bug, or do I get something wrong?

[nji9]

No comment - so it seems to be actually a bug viewtopic.php?t=50144

[xnview]

please describe how to reproduce?

[nji9]

please describe how to reproduce?

Actually that was my aim with my first post
(and additionally in the bug report viewtopic.php?t=50144)...

OK, again:

Category Filter pane, no selection made ==> all images shown.
Select Alt-Click for some category.
What happens: Nothing.
Would should happen: Show all images NOT assigned to selected category.

Further description/ reasoning see above and in the bug report.