Thanks. Yes, I know this feature.
The issue is that you need to do this action for each folder, i.e. it is impossible to ctrl (or shift) select a number of folders and then open in the same (scratch) contact sheet.
Example: if you wish to open 10-15 folders (out of a LOT) then you have to rmb add to same contact sheet 10-15 times.
Maybe something for the next release.
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