Added a test project for the reproduction of Issue nunit#4658.

Issue4658/.runsettings

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+<?xml version="1.0" encoding="utf-8"?>
+<RunSettings>
+  <NUnit>
+    <DefaultTimeout>1200000</DefaultTimeout>
+  </NUnit>
+</RunSettings>

Issue4658/ApartmentTest.csproj

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+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net8.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+
+    <IsPackable>false</IsPackable>
+    <IsTestProject>true</IsTestProject>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.9.0" />
+    <PackageReference Include="NUnit" Version="4.1.0" />
+    <PackageReference Include="NUnit3TestAdapter" Version="4.5.0" />
+  </ItemGroup>
+
+</Project>

Issue4658/ApartmentTest.sln

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+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 17
+VisualStudioVersion = 17.8.34525.116
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "ApartmentTest", "ApartmentTest.csproj", "{C94EF6CC-69E7-4FD2-BAC7-4F478F41C785}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{C94EF6CC-69E7-4FD2-BAC7-4F478F41C785}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{C94EF6CC-69E7-4FD2-BAC7-4F478F41C785}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{C94EF6CC-69E7-4FD2-BAC7-4F478F41C785}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{C94EF6CC-69E7-4FD2-BAC7-4F478F41C785}.Release|Any CPU.Build.0 = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+	GlobalSection(ExtensibilityGlobals) = postSolution
+		SolutionGuid = {86F44442-904E-4CCC-9204-593A89740BC3}
+	EndGlobalSection
+EndGlobal

Issue4658/README.md

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+Test project for [Issue #4658](https://github.com/nunit/nunit/issues/4658).
+
+To reproduce, either run the test `ApartmentStateShouldBeSTA` from Visual Studio 2022, or open a command prompt from this directory and run the following:
+
+```
+dotnet test -s .runsettings
+```

Issue4658/UnitTest1.cs

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+using NUnit.Framework;
+
+namespace ApartmentTest
+{
+    [TestFixture, Apartment(ApartmentState.STA)]
+    public class Tests
+    {
+        [Test]
+        public void ApartmentStateShouldBeSTA()
+        {
+            Assert.That(Thread.CurrentThread.GetApartmentState(), Is.EqualTo(ApartmentState.STA));
+        }
+    }
+}