.NET: Xcode 13.3

We're excited to announce our first SDK release for .NET! After many years of work we've moved to .NET, where among other things we'll get an updated Base Class Library, which is unified across all .NET platforms.

Note: these are the base SDKs that add support for the platforms in question, for MAUI (which is built on top of our SDKs), go here instead: https://docs.microsoft.com/en-us/dotnet/maui/.

This release consists of the following versions:

• iOS: 15.4.303
• tvOS: 15.4.303
• macOS: 12.3.303
• Mac Catalyst: 15.4.303

Full release notes: https://github.com/xamarin/xamarin-macios/wiki/.NET-release-notes-Xcode-13.3
Known issues: https://github.com/xamarin/xamarin-macios/wiki/Known-issues-in-.NET
Breaking changes: https://github.com/xamarin/xamarin-macios/wiki/Breaking-changes-in-.NET