APPLE INSIDER
Apple’s first macOS Big Sur 11.3 beta contains new additions like deeper customization options in Safari, support for the latest Xbox and PlayStation controllers, and more.

The company seeded the first beta of macOS Big Sur 11.3 to registered developers on Tuesday, just a day after releasing macOS 11.2 and the first beta versions of iOS 14.5, watchOS 7.4, and tvOS 14.5.
Source: APPLE INSIDER