Server version: 18.104.22.168
Logs: Available upon request
I have some items that will not add to any collections. I locate the item (movie or TV show) in the library or by searching, click the checkbox in the web interface, Choose "Add to collection", then either choose an existing collection or type a new collection name, then click Ok. For affected media items, it is not added to the collection. If a new collection was being created, it is created without any new media items in it.
For unaffected media items, the item is added without issue.
I can't figure out any rhyme or reason to which items are affected. The only thing they seem to have in common is that they were all previously in a "To Watch" collection and then vanished from there some time ago (maybe 6-12 months).
I saw that some collection fixes were being planned for the latest 22.214.171.124 release, so I waited until now to report it. After upgrading this morning, I'm still seeing this problem. As far as I know, none of the affected items are "multiple version" media items.