Copy is not reusing instance

[ajdust]

The 'Copy JsonSerializerOptions' section comes right after 'Reuse JsonSerializerOptions instances'. This has been confused as a recommendation to use 'new JsonSerializerOptions(staticInstance)' to reuse JsonSerializerOptions instances. Recommend noting that using this constructor is not the same as a static instance, as the cache of JsonSerializerOptions is not copied to the new one.

dotnet/runtime#30445 (comment)

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Document Details

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• ID: 279af375-abfa-e10e-046a-625cc14826be
• Version Independent ID: 1df274ad-ecf0-49e7-90c6-e6f05dce0788
• Content: How to instantiate JsonSerializerOptions with System.Text.Json
• Content Source: docs/standard/serialization/system-text-json-configure-options.md
• Product: dotnet-fundamentals
• GitHub Login: @tdykstra
• Microsoft Alias: tdykstra

[tdykstra]

Thanks for pointing that out. I'm adding a note about this in #29314 .