Same issue. Using MacBook Pro 13" Late 2013. Close laptop itself and use two monitors for display. One monitor is thunderbolt 2 to HDMI and displays fine post upgrading from Catalina to Big Sur. The other monitor is just HDMI and is now a smaller display size despite saying 1920x1200 I have black bars on top/bottom/left/right. I restarted manually and it didn't work. I restarted with just the 2nd monitor connected (the one with black bars) and it loads full screen as it is supposed to. The second I plug in the second monitor, my mac restarts and says it ran into an error. After restarted, same situation.
NINJA_TAC0
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