If I create a Collection I would like to be able to include both Films and TV Shows (And even Music if possible). Example: I have a Star Trek Collection with the films in it I cannot add the Star Trek TV Shows to the same collection. I would like to.
Thanks
Simply create a collection of the same name in each library.
This way your media will show up as related content in the collection. The support article on collections even gives an example based on Star Wars (movie collection showing some series and soundtrack albums as related content)
Here’s some other examples 
Also works the other way around…
Ahh, got it. Jutest tested it and it works. Missed that.
In the meantime I am battling an issue where all of a sudden I cannot delete collections (“There was a problem deleting this item”). Just started. Server has been running about 2 years with never a problem until today. But that’s a different issue.
Thank you for your help!
That’s a known issue. A member of the Plex team commented it’ll be addressed with one of the next releases for the Plex Media Server (PMS 1.22.2); no ETA.
As for having different media in the same collection…
I actually like how this is currently handled – content is linked but still recognizably of a different type.
Just let me know if you still want to go for a fully merged collection use case or if this suggestion is now obsolete 
This is fine and “obsolete”. Also, thanks for the heads up on PMS 1.22.2.
It’s the little things. Much appreciated.
Early 2021 clean-up: implemented (related collections)
