Feature Idea (one per thread):
When adding a lot of links to a group, often you do not want to select the same document twice
If a link appears in a group, an option to hide any documents which have already been selected by other items within the same group. Deselecting this option would allow the group item link to be selected in the same way it currently works.
Issue that it solves:
This is a quality of life improvement for editors, ensuring the same items don't accidentally get added to a list multiple times