runtime: BUG: Json.NET converter for IPAddress does not work in .NET Core 3.0 specifically

Using Json.NET converters within the .NET Core 3.0 runtime fails. However in .NET Core 2.2 or .NET Framework 4.8 it works fine.

It seems like some “Type” is not coming through correctly.

.NET Core versions are both using the same .NET Standard 2.0 Json.NET lib. This makes me think its a .NET runtime issue of some kind or another but I can’t be sure.

Download this example project that you can reproduce the issue with. https://vrstudios-my.sharepoint.com/:u:/p/andrew_witte/ETIlqlXTlu1Moiz2Q2MYsAUBIje5Z96Zij7xGPL3wAO6wA?e=sz1oDH

Win10 x64 1904 OS Build: 18362.356 Visual Studio 2019 16.3.0 Preview 3.0 .NET Core 3.0.100-preview9-014004 .NET Core 2.2.104

Here are all my available .NET Core versions installed.

1.0.0-preview1-002702
1.0.0-preview2-003121
1.0.0-preview2-003131
1.0.1
1.0.2
1.0.3
1.0.4
1.1.0
2.0.2
2.0.3
2.1.100
2.1.101
2.1.102
2.1.103
2.1.104
2.1.2
2.1.200
2.1.201
2.1.202
2.1.4
2.1.400
2.1.401
2.1.402
2.1.403
2.1.500
2.1.502
2.1.503
2.1.504
2.1.505
2.1.507
2.1.508
2.1.509
2.1.602
2.1.604
2.1.700
2.1.700-preview-009618
2.1.701
2.1.800
2.1.800-preview-009677
2.1.800-preview-009696
2.1.801
2.1.802
2.2.101
2.2.103
2.2.104
3.0.100-preview9-014004

VS info

Microsoft Visual Studio Community 2019 Preview
Version 16.3.0 Preview 3.0
VisualStudio.16.Preview/16.3.0-pre.3.0+29230.61
Microsoft .NET Framework
Version 4.8.03752

Installed Version: Community

Visual C++ 2019   00435-60000-00000-AA947
Microsoft Visual C++ 2019

Application Insights Tools for Visual Studio Package   9.1.00815.1
Application Insights Tools for Visual Studio

ASP.NET and Web Tools 2019   16.3.277.18560
ASP.NET and Web Tools 2019

ASP.NET Core Blazor Language Services   16.0.19227.01

ASP.NET Web Frameworks and Tools 2019   16.3.277.18560
For additional information, visit https://www.asp.net/

Azure App Service Tools v3.0.0   16.3.277.18560
Azure App Service Tools v3.0.0

Azure Functions and Web Jobs Tools   16.3.277.18560
Azure Functions and Web Jobs Tools

C# Tools   3.3.1-beta3-19430-03+fa8e2c9b566e4471a3509fc63d7baca0a2a6d30b
C# components used in the IDE. Depending on your project type and settings, a different version of the compiler may be used.

Common Azure Tools   1.10
Provides common services for use by Azure Mobile Services and Microsoft Azure Tools.

ConvertToDevExtremeCommand Extension   1.0
ConvertToDevExtremeCommand Visual Studio Extension Detailed Info

IntelliCode Extension   1.0
IntelliCode Visual Studio Extension Detailed Info

Microsoft Azure Tools   2.9
Microsoft Azure Tools for Microsoft Visual Studio 0x10 - v2.9.20816.1

Microsoft Continuous Delivery Tools for Visual Studio   0.4
Simplifying the configuration of Azure DevOps pipelines from within the Visual Studio IDE.

Microsoft JVM Debugger   1.0
Provides support for connecting the Visual Studio debugger to JDWP compatible Java Virtual Machines

Microsoft Library Manager   2.0.83+gbc8a4b23ec
Install client-side libraries easily to any web project

Microsoft MI-Based Debugger   1.0
Provides support for connecting Visual Studio to MI compatible debuggers

Microsoft Visual C++ Wizards   1.0
Microsoft Visual C++ Wizards

Microsoft Visual Studio Tools for Containers   1.1
Develop, run, validate your ASP.NET Core applications in the target environment. F5 your application directly into a container with debugging, or CTRL + F5 to edit & refresh your app without having to rebuild the container.

Microsoft Visual Studio VC Package   1.0
Microsoft Visual Studio VC Package

NuGet Package Manager   5.3.0
NuGet Package Manager in Visual Studio. For more information about NuGet, visit https://docs.nuget.org/

ProjectServicesPackage Extension   1.0
ProjectServicesPackage Visual Studio Extension Detailed Info

SQL Server Data Tools   16.0.61908.27190
Microsoft SQL Server Data Tools

Test Adapter for Boost.Test   1.0
Enables Visual Studio's testing tools with unit tests written for Boost.Test.  The use terms and Third Party Notices are available in the extension installation directory.

Test Adapter for Google Test   1.0
Enables Visual Studio's testing tools with unit tests written for Google Test.  The use terms and Third Party Notices are available in the extension installation directory.

TypeScript Tools   16.0.10821.2002
TypeScript Tools for Microsoft Visual Studio

Visual Basic Tools   3.3.1-beta3-19430-03+fa8e2c9b566e4471a3509fc63d7baca0a2a6d30b
Visual Basic components used in the IDE. Depending on your project type and settings, a different version of the compiler may be used.

Visual F# Tools 10.4 for F# 4.6   16.3.0-beta.19421.2+9f51ac5290b1dfc5dc434841d61b2ac31997ea8c
Microsoft Visual F# Tools 10.4 for F# 4.6

Visual Studio Code Debug Adapter Host Package   1.0
Interop layer for hosting Visual Studio Code debug adapters in Visual Studio

Visual Studio Tools for CMake   1.0
Visual Studio Tools for CMake

Visual Studio Tools for CMake   1.0
Visual Studio Tools for CMake

Visual Studio Tools for Containers   1.0
Visual Studio Tools for Containers