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[ 8.0.100-alpha.1.23060.3] mRemoteNg app Error creating window handle error while creating Combobox

See original GitHub issue

.NET version

.NET SDK:
 Version:   8.0.100-alpha.1.23060.3
 Commit:    c5ebd18478

Runtime Environment:
 OS Name:     Windows
 OS Version:  10.0.19045
 OS Platform: Windows
 RID:         win10-x64
 Base Path:   C:\Program Files\dotnet\sdk\8.0.100-alpha.1.23060.3\

Host:
  Version:      8.0.0-alpha.1.23058.2
  Architecture: x64
  Commit:       5da4a9e919

.NET SDKs installed:
  8.0.100-alpha.1.23060.3 [C:\Program Files\dotnet\sdk]

.NET runtimes installed:
  Microsoft.AspNetCore.App 8.0.0-alpha.1.23058.7 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 8.0.0-alpha.1.23058.2 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.WindowsDesktop.App 8.0.0-alpha.1.23057.1 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

Did it work in .NET Framework?

N/A

Did it work in any of the earlier releases of .NET Core or .NET 5+?

Verify Scenarios:

Windows 10 21H2 AMD64 + 8.0.100-alpha.1.23061.8: Fail 2). Windows 10 21H2 AMD64 + dotnet-sdk-8.0.100-alpha.1.23060.31: Fail
Windows 10 21H2 AMD64 + dotnet-sdk-7.0.102-win-x64: Pass 4). Windows 10 21H2 AMD64 + dotnet-sdk-6.0.405-win-x64: Pass

Issue description

When test 3rd party mRemoteNg app with .NET 8 runtime, exception “error creating window handle error” shows while creating Combobox.

Application Name: mRemoteNg(1.77.3) OS: Windows 10 21H2 CPU: X64 .NET Build Number: dotnet-sdk-8.0.100-alpha.1.23060.3 App or App Source checking at: https://devdiv.visualstudio.com/DevDiv/_workitems/edit/1717274 Github Link: https://github.com/mRemoteNG/mRemoteNG

Steps to reproduce

The machine only has 8.0 installed. And DOTNET_ROLL_FORWARD_ON_NO_CANDIDATE_FX=2 is set.

1.Copy app from AppSource\SourceShare\mRemoteNG to machine 2.Launch the app from mRemoteNG.exe 3.If you see update window, click ask me later 4.Click Tools=>Port Scan

Expected Result: Port Scan Tab should open without error

Actual Result:

Exception: Exception Message “Error creating window handle.”

Stack trace
   at System.Windows.Forms.NativeWindow.CreateHandle(CreateParams cp)
   at System.Windows.Forms.Control.CreateHandle()
   at System.Windows.Forms.ComboBox.CreateHandle()
   at System.Windows.Forms.Control.CreateControl(Boolean ignoreVisible)
   at System.Windows.Forms.Control.CreateControl(Boolean ignoreVisible)
   at System.Windows.Forms.Control.CreateControl()
   at System.Windows.Forms.Control.WmShowWindow(Message& m)
   at System.Windows.Forms.Control.WndProc(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
   at System.Windows.Forms.NativeWindow.Callback(HWND hWnd, WM msg, WPARAM wparam, LPARAM lparam)

Environment
OS: Microsoft Windows NT 10.0.19045.0
mRemoteNG Version: 1.77.3
Edition: MSI
Cmd line args:

Findings: We think this error happens when creating combobox control, app is overriding OnCreateControl, when we remove DrawMode = DrawMode.OwnerDrawFixed, issue does not repro. In this file: mRemoteNG-1.77.3-dev\mRemoteNG\UI\Controls\mrngComboBox.cs

 protected override void OnCreateControl()
  {
            base.OnCreateControl();
            _themeManager = ThemeManager.getInstance();
            if (!_themeManager.ActiveAndExtended) return;
            BackColor = _themeManager.ActiveTheme.ExtendedPalette.getColor("ComboBox_Background");
            ForeColor = _themeManager.ActiveTheme.ExtendedPalette.getColor("ComboBox_Foreground");
             DrawMode = DrawMode.OwnerDrawFixed;  //if we remove, issue does not repro
            SetStyle(ControlStyles.OptimizedDoubleBuffer |
                     ControlStyles.UserPaint, true);
}

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