Entire top-level program file is always faded with IDE0051 "Private member '$Program.$Main' is unused."

[jnm2]

Version Used: 16.7-p3.1

The program runs fine. There's just an errant IDE0051 in the error list and fading the entire file:

If you trigger the lightbulb or click 'Show potential fixes,' you get a gold bar saying CSharpRemoveUnusedMembersCodeFixProvider crashed:

System.NullReferenceException : Object reference not set to an instance of an object.
   at Microsoft.CodeAnalysis.Editing.SyntaxGenerator.PreserveTrivia[TNode](TNode node,Func`2 nodeChanger)
   at Microsoft.CodeAnalysis.CSharp.CodeGeneration.CSharpSyntaxGenerator.RemoveNode(SyntaxNode root,SyntaxNode node,SyntaxRemoveOptions options)
   at Microsoft.CodeAnalysis.Editing.SyntaxEditor.RemoveChange.Apply(SyntaxNode root,SyntaxGenerator generator)
   at Microsoft.CodeAnalysis.Editing.SyntaxEditor.GetChangedRoot()
   at async Microsoft.CodeAnalysis.CodeFixes.SyntaxEditorBasedCodeFixProvider.FixAllWithEditorAsync(<Unknown Parameters>)
   at async Microsoft.CodeAnalysis.CodeActions.CodeAction.GetChangedSolutionAsync(<Unknown Parameters>)
   at async Microsoft.CodeAnalysis.CodeActions.CodeAction.ComputeOperationsAsync(<Unknown Parameters>)
   at async Microsoft.CodeAnalysis.CodeActions.CodeAction.GetPreviewOperationsAsync(<Unknown Parameters>)
   at async Microsoft.CodeAnalysis.Editor.Implementation.Suggestions.SuggestedAction.GetPreviewResultAsync(<Unknown Parameters>)
   at async Microsoft.CodeAnalysis.Editor.Implementation.Suggestions.SuggestedActionWithNestedFlavors.<>c__DisplayClass11_0.<GetPreviewAsync>b__0(<Unknown Parameters>)
   at async Microsoft.CodeAnalysis.Extensions.IExtensionManagerExtensions.PerformFunctionAsync[T](<Unknown Parameters>)
   at Microsoft.VisualStudio.Telemetry.WindowsErrorReporting.WatsonReport.GetClrWatsonExceptionInfo(Exception exceptionObject)

Repro

It repros with net5.0 also, and it doesn't change anything when Program.cs is complex.

using System;

Console.WriteLine("Hi!");

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>netcoreapp3.1</TargetFramework>
    <LangVersion>preview</LangVersion>
  </PropertyGroup>

</Project>

dotnet --info

.NET SDK (reflecting any global.json):
 Version:   5.0.100-preview.4.20258.7
 Commit:    65f0fc2cad

Runtime Environment:
 OS Name:     Windows
 OS Version:  10.0.19041
 OS Platform: Windows
 RID:         win10-x64
 Base Path:   C:\Program Files\dotnet\sdk\5.0.100-preview.4.20258.7\

Host (useful for support):
  Version: 5.0.0-preview.4.20251.6
  Commit:  47ec733ba7

.NET SDKs installed:
  2.1.802 [C:\Program Files\dotnet\sdk]
  3.0.101 [C:\Program Files\dotnet\sdk]
  3.1.301 [C:\Program Files\dotnet\sdk]
  3.1.400-preview-015178 [C:\Program Files\dotnet\sdk]
  5.0.100-preview.4.20258.7 [C:\Program Files\dotnet\sdk]

.NET runtimes installed:
  Microsoft.AspNetCore.All 2.1.19 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.App 2.1.19 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 3.0.1 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 3.1.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 3.1.5 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 5.0.0-preview.4.20257.10 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 2.1.13 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.19 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 3.0.1 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 3.1.2 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 3.1.5 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 5.0.0-preview.4.20251.6 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.WindowsDesktop.App 3.0.1 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 3.1.2 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 3.1.5 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 5.0.0-preview.4.20251.1 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]