Usecase:
If you want multiple categories SET or UNSET by drawing the downholded mouse above them
the collapsed categories are not effected by the setting.
You have to expand all of them manually.
It would be nice to have an "expand all"/ "collapse all" in their context menu.
Using category system: Set category SET, set category to NOTSET multiple categories for filtering
Moderators: helmut, XnTriq, xnview