Berliner Sparkasse Onlinebanking FAQ: »Why do I get the message ‘mobile device, can’t perform smsTAN money transfer when using my Desktop computer.« »A possible cause is the display resolution. Your computer is being detected as a mobile device by our online banking system. smsTAN is not working from a mobile device. Solution: Change the display resolution.«
So 1920×1080 work, but 1080×1920 doesn’t.