I was deleting a Temp state var and was looking for dependencies to handle.
I could not find a few - they were ghosts. 
For instance it has a dependency on a custom column in a table:
But that column was deleted long ago.
The next two are Module Inputs that I deleted when I refactored them a week ago.
I guess it is the right time of year for the dead to walk among us! 
Spooky, indeed 
I know custom columns and module inputs don’t really get deleted the way we’d expect them to…but I don’t know much else past that.
I’ll ask eng! In the meantime, is this blocking any development?
Let me amend my original, I did find the custom column reference, so the issue is only with the Modules.
I do notice that on Columns if you change your query to remove a column that you had configured and then add it back in the previous config is kept for some period of time. I like that. Queries do a similar thing as you switch back and forth from SQL and GUI modes. I have learned to like that.
Maybe something similar going on with Modules I have not otherwise noticed?
And no, it is not holding me up at all, just an FYI really.
Talking to eng about this!