I've been using Plex for years, but run in "Offline" mode, where I don't sign in with my Plex account, but I let local devices connect (like Amazon Fire TV Stick, web browsers, etc. that are on my local LAN). There has never been an issue besides discovery doesn't work (meaning I have to go to the server IP address). Now, over the last month or so, I've noticed that my media artwork is either disappearing or not showing up at all with new media (TV shows and movies). The metadata is showing up fine, just artwork isn't. I honestly have been pulling my hair out trying to figure this out. I ended up trying the web browser on the server itself and magically, EVERYTHING shows up just fine. It's just on other devices that only half the posters show up for. Playback works flawlessly on all devices, the interface works normally on all, and metadata works fine. Just artwork is spotty on all devices (except the server itself). Ideas?
What I've tried:
1. Uninstalled/reinstalled Plex.
2. Opened 32400 on the server.