When I append a group of objects they don't show up

I linked a group into my .blend and then I decided I want to append instead and make some local changes.
I unlinked the group (deleted) but I can’t append that group now!
It’s like Blender remembers that a group with that name once existed in linked form and it’s hanging onto that memory.
Where can I find the residual data and clear it so I can append?

I found the answer. Just deleting the linked data is not enough. You must also save, close, and re-open the file.
Then you can append it.
One of those cases with lingering unused data block trickery.