Hey,
Whenever i update my Plex Media Server all thumbnails that i have set manualy somehow get lost, they are just showing as empty (grey). This happened now twice, so i dont think it is a bug in a certain Version of Plex.
When i restart the server the thumbnails dont get lost, so i think they are getting stored propperly.
Im running Plex on a OMV (Open Media Vault) Server
Thanks for your answer 
Yes i am talking about Posters, but also about Backrounds.
I am selecting the images by clicking on the edit button (the one with the little pen on it) → Poster/Backround and then i just uplaod a local file.
Does this Local Media Asset Trick also works for Photo Libraries? This is where most of my custum images end up beeing used (I have a lot of digital Comics on my Plex).
Yep, just tried it with some poster.jpg, doesnt work for photos (also theres no Local Media Assets in the Agends ssection for photos).
This might be something fairly easy to implement for the next Plex update wouldnt it?
