MacOS Big Sur build 20B5012d

macOS Big Sur build 20B5012d is the official Beta 1 release of macOS Big Sur 11.0.1, which was released to Apple developers on 2020-10-28. This build adds 40 new wallpapers, which are the same ones that can be found in iOS 14.2 beta. It was also released as the first public beta of this release one day later on 2020-10-29.