Apple has released fourth developer beta of macOS Catalina. Update came three weeks after 3rd developer beta was released.
There are no signs of fourth developer beta for iOS 13 and watchOS 6. Apple may release them later today or we might have to wait a bit longer for them.
Fourth developer beta for macOS Catalina has an incompatibility with Xcode 11 beta 3. Will be fixed with the fourth beta of Xcode.
Using Xcode 11 beta 3 with macOS Catalina beta 4 will prevent SwiftUI previews from working. Update to Xcode 11 beta 4 when it becomes available.
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