So this rarely happens, but it's really quite annoying when it does.
There are times that I set my Spotify on my Android phone to "offline" - especially before a long business trip. What happens is that somewhere, Spotify decides to log itself out of my account, and basically traps me in the login screen saying that I'm offline even if I'm connected over Wi-Fi (just because I set it to offline mode).
I'm thinking this is some sort of weird interaction that happens between turning on "Offline mode" and updating the software, but it's almost laughably stupid that this kind of error is even possible.
I usually end up wiping the cache from my phone, logging in again and redownloading all my offline playlists, which is quite irritating. Is there a workaround for this? Or is Spotify just... mentally damaged?