When I'm signing into the new interface (v15.46.5 ), I enter my username and password, then the code from Authenticator, and then it just sits there.
Closing and reopening brings up the same authentication code screen, still sitting there.
If I force the app closed from the system tray icon, after I restart it, it's signed in.
If it was just the once, I wouldn't mind, but it's every day because it keeps signing me out despite me ticking the box to "stay signed in".