Everything in the stack menu works on multiple items; when I select multiple images in stacks and select show more from this stack it opens a new tab with all members of the slected stacks.
This does not apply to "make this the stacks top item". That only works for the first selected image. Is there a way to select an image for a number of stacks and mark it as the top item at once? I have several hundreds to do
Make the top item is indeed no multiple task.
But, in the preferences->cataloging->stacking you can define the stack detection rules, including how the top item should be picked. That may help here.
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