Ability to make linked collections local

Hi everyone!
I have a complex scene that consists of objects linked from external .blend files.
Part of objects are single objects, linked as they are and instanced. And part of them consist of several separate objects so I linked them as collections so they could appear as a whole.
At some point I will have to modify all those objects in this scene (for creating a lightmap UV). But.
The problem is I can not make linked collections local and single-user. None of it’s menu items don’t do anything.

And I know there were several topics like these on this forum, but none of them (what I found) were answered.
Thank you!

Hello !

I think the problem comes from the fact that you are using different way to link data…
I’m pretty sure it’s possible to localize everything, but I’d prefer to test a bit to be sure.

Can you provide a test scene that represent all your test cases ? maybe not with your actual scene, but a few cubes and spheres. That way I can give it a try and tell you exactly what I did !