To clean up my scene, I used Right-Click > Unlink in the Outliner, but now I want the collections back.
I can find them by switching to the Blender File context in the Outliner, but the Right-Click > Link to Scene doesn't appear to do anything.
Instance to Scene makes something that acts like a Collection Instance, so I can't edit the contents.
I also can't click and drag, or copy paste. What am I doing wrong?