Users have already complained about problems with external displays under macOS Big Sur 11.1. However, these problems still seem to exist under macOS Big Sur 11.2.
Some macOS Big Sur users who are using the 11.1 update and the recently released 11.2 update are experiencing ongoing issues with external displays. This is according to various reports on Reddit, Twitter and Apple's support forum Based on the reports, these appear to be two separate issues, but both are related to external displays. The issue started on macOS Big Sur 11.1 and was not fixed in the subsequent update, but rather made worse. The first issue causes USB-C ports to not recognize external monitors, rendering external displays unusable. This appears to affect both DisplayPort and HDMI displays connected directly or via hubs and adapters. As one user explains on Reddit:
macOS Big Sur display problems: There seems to be no solution
Upgrading to 11.2 broke my second external monitor port. Primary monitor LG Ultrafine 4k (Mac version) connected via Thunderbolt. Secondary monitor (same model) connected via HDMI->DisplayPort adapter (BENFEI) then DisplayPort->USB-C cable stopped working after update (worked fine on 11.1 before update).
macOS seems to recognize the monitor and resolution because it shows up in the display settings and Apple Support was able to see both screens in my computer. It's almost as if the signal to turn on the monitor is not being sent.
The second error causes resolution issues with external monitors that are unable to work at the full 4K resolution of 60 Hz but are stuck at 30 Hz. In some other cases, a 4K display is only recognized as a 1080p monitor. According to initial findings, 16-inch MacBook Pro models seem to be primarily affected by the display issue. However, there are also statements that include other Mac devices. There does not seem to be a solution at the moment. It remains to be seen when Apple will fix the problem with a software update. (Photo by taborov / Bigstockphoto)