Me too. I'm running Big Sur on the new MBP 13 in w/M1 chip. Am also connected to an ultra wide LG Display. Am experiencing 2 distinct issues: 1. After sleep, logging in on big display (main screen) - the bkgnd image is the same size and shape as if I were logging into laptop. In other words, it's like looking at the laptop display footprint on the larger monitor or a square within a square. 2. Going Full Screen on Chrome 87.0.4280.88 (arm 64 build). Just to be clear, I have this setup for email/chat/calendar on laptop display. And when in FS I see annoying flickering. This doesn't happen when NOT in FS mode.
LizM
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