Can't locate original of instanced collection

I’m run into a bit of a weird situation whereby I have an instanced collection, but I can’t locate the original collection so I can go inside and edit the meshes/objects. I’ve searched with the outliner in Blender File view, but to no avail. The other thing is I’m pretty sure the collection was initially linked in from another file, but again, it’s not listed at the bottom of the outliner in Blender file view…