Multiple fields are marked “This is the default behavior”: Default, NotSet

Both `Default` and `NotSet` are documented as:

> This is the default behavior.

Please explain how and what circumstance each one is the default behavior.

I am going to guess that `Default` is the default value set by code somewhere. It would also seem that `NotSet` is documented as default because it’s what you get from this C# expression: `default(FcnMode)` or for any uninitialized field.

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#### Document Details

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* ID: 75aff974-f324-1fb1-d9bb-fce579f1db80
* Version Independent ID: ebc004a9-bc4a-b147-7e3e-7f650f51d6f9
* Content: [FcnMode Enum (System.Web.Configuration)](https://docs.microsoft.com/en-us/dotnet/api/system.web.configuration.fcnmode?redirectedfrom=MSDN&view=netframework-4.7.2)
* Content Source: [xml/System.Web.Configuration/FcnMode.xml](https://github.com/dotnet/dotnet-api-docs/blob/master/xml/System.Web.Configuration/FcnMode.xml)
* Product: **dotnet-api**
* GitHub Login: @dotnet-bot
* Microsoft Alias: **riande**