HurryHead1457 After entering email+password in the Facebook app, it opens the browser version of Facebook saying this login attempt must be approved on another device. After approval, you become logged into Facebook ... in the browser. If you go back into the app, it's still not logged in. So it's uhh kind of impossible to log into the app. I'm not sure if that's GOS-specific? Is there some way to make YouTube not share its logged in account with the rest of the profile apps, besides creating two profiles?
HurryHead1457 Facebook glitched itself out of the glitch: after a few sequential runs and failures to "really" log in, the app showed a few more weird errors and finally started working properly.