Update table of differences between Newtonsoft.Json / STJ

[layomia]

Doc Link

Contract customization enables new workarounds we can provide samples for:

• Support for System.Runtime.Serialization attributes - can expand/polish user sample https://github.com/zcsizmadia/ZCS.DataContractResolver
• MissingMemberHandling - Add support for MissingMemberHandling to System.Text.Json runtime#37483 (comment)

We should consider updating the feature article with this info as well - https://learn.microsoft.com/en-us/dotnet/standard/serialization/system-text-json/custom-contracts.

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We should also specify that the following are not supported by-design and we won't support them in the future:

Feature	Status
Allow property names without quotes	❌ Not supported
Allow single quotes around string values	❌ Not supported
Allow non-string JSON values for string properties	❌ Not supported
TypeNameHandling.All global setting	❌ Not supported

FYI @eiriktsarpalis @krwq

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Document Details

⚠ Do not edit this section. It is required for learn.microsoft.com ➟ GitHub issue linking.

• ID: 6b74d77c-33e1-d44c-18c6-bd0b612f74de
• Version Independent ID: 9c6a7135-eb75-21a9-1d27-0880459523ca
• Content: Migrate from Newtonsoft.Json to System.Text.Json - .NET
• Content Source: docs/standard/serialization/system-text-json/migrate-from-newtonsoft.md
• Product: dotnet-fundamentals
• GitHub Login: @gewarren
• Microsoft Alias: gewarren

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Associated WorkItem - 97031