What's new in .NET 6 RC2 [WIP]

[leecow]

What's new in .NET 6 RC2

This issue is for teams to highlight work for the community that will release .NET 6 RC2

To add content, use a new conversation entry. The entry should include the team name and feature title as the first line as shown in the template below.

## Team Name: Feature title

[link to the tracking issue or epic item for the work]

Tell the story of the feature and anything the community should pay particular attention 
to be successful using the feature.

Preview 1: #5853
Preview 2: #5889
Preview 3: #5890
Preview 4: #6098
Preview 5: #6099
Preview 6: #6325
Preview 7: #6444
RC1: #6569

[jkotas]

.NET 6 RC2 has API breaking changes. For example, the APIs for Json source generators have changed (dotnet/runtime#59042). The binaries compiled against .NET 6 RC1 are not supported on .NET 6 RC2.

[karelz]

We added API on System.Net.Uri (new constructor overloads and UriCreationOptions) to enable customers process Uris transparently, without normalization/canonicalization of path and query - dotnet/runtime#59099 (comment) & dotnet/runtime#59173

[karelz]

.NET 6 RC2 brings WinHttpHandler support for TLS 1.3 on Windows 11+ - dotnet/runtime#58587

[Sergio0694]

Sharing these two new APIs here for tracking, as they've been accidentally missed in previous blog posts:

• DependentHandle (see What's new in .NET 6 RC1 [WIP] #6569 (comment))
• HMAC one-shot methods (see What's new in .NET 6 RC1 [WIP] #6569 (comment))

[layomia]

.NET 6 RC2 has API breaking changes. For example, the APIs for Json source generators have changed (dotnet/runtime#59042). The binaries compiled against .NET 6 RC1 are not supported on .NET 6 RC2.

For additional info on the motivation and mitigation for the JSON src-gen changes, see the breaking change doc - https://docs.microsoft.com/en-us/dotnet/core/compatibility/serialization/6.0/json-source-gen-api-refactor?branch=pr-en-us-26222 and original issue dotnet/docs#26200. We could cite the official doc in this blog post.

[cston]

C# compiler: Avoid several breaking changes from inferred types of lambdas and method groups

Overload resolution has been updated in the Roslyn C# compiler to prefer overloads where conversions and method type argument inference do not involve inferred types of lambda expressions or method groups (see dotnet/roslyn#56341). This resolves several breaking changes in .NET 6 RC1.