About a week ago I updated multiple apps using the “update all selected” option in the web UI. The next time I looked in the web UI the list was completely empty despite most of my apps still working just fine. The only app that isn’t still working is lidarr. Even through reboots, all of the apps (except lidarr) fire right back up and work fine.
If it helps, I installed a random app I didn’t have before and it regenerated some files like the metadata.yaml which was previously empty. Some apps started appearing in the UI after that.
So since my install of Lidarr wasn’t working, I went ahead and set up a new copy of it. As soon as I did that all of my other apps reappeared in the UI.
I have no idea what the cause was or why that fixed it though.