When in the Develop module my second monitor becomes blurry. This happened at the time of 10.2 update. I am running iMacPro and MacOS Big Sur 11.2.3. Interestingly, LR system info incorrectly shows I'm running MacOS 10.16.0.
It seems turning off acceleration has made second monitor useable again. I am running latest version of MacOS which is supposed to include Radeon driver updates as well. To reiterate, all was well until LrC 10.2 update.
Also, should I be concerned that LrC System Info does not reflect I am running Big Sur?
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"Also, should I be concerned that LrC System Info does not reflect I am running Big Sur?"
No. Here's what LR and Mac OS report:
LR Help > System Info: Operating system: Mac OS 10; Version: 10.16.0 [20D91]
:red_apple: > About This Mac > System Report > System Version: macOS 11.2.3 (20D91)
LR may be getting the version from /System/Library/CoreServices/SystemVersion.plist, which shows 10.16 (20D91). Google shows threads discussing this during the beta of Big Sur, but I didn't see any authoritative answer why SystemVersion.plist still shows an incorrect version.