Docs show some APIs added in .NET 9 preview as available in .NET 8

[Jozkee]

This API is only available for 9. Same happens for IndentCharacter and IndentSize. Not sure if it's a bug in the xml content or in the rendering tool.

cc @gewarren

[gewarren]

@Jozkee It shows that way because the package can be used on downlevel frameworks - https://www.nuget.org/packages/System.Text.Json/9.0.0-preview.5.24306.7#supportedframeworks-body-tab. Do you think this is too confusing? Eventually the applies to table will differentiate package-provided versions from built-in versions, which will help a bit.

[gewarren]

Related to #9919, #9868.

[Jozkee]

Do you think this is too confusing?

I think is not obvious how the specified versions are supported. Looks like the preview package targets both current (9.0) and previous (8.0) versions, which I forgot. For 7.0, netstandard2.0 version is used.

Eventually the applies to table will differentiate package-provided versions from built-in versions, which will help a bit.

That would be nice!