I think it worth to mention, that in .NET 9.0 there are new APIs to enable Windows Dark mode in Windows Forms apps. I've tried it on WireSockUI project, and with few extra changes in the project, it works. It's not perfect, but it works without much effort:
// Add to Program.Main()
Application.SetColorMode(SystemColorMode.System);

I think it worth to mention, that in .NET 9.0 there are new APIs to enable Windows Dark mode in Windows Forms apps. I've tried it on WireSockUI project, and with few extra changes in the project, it works. It's not perfect, but it works without much effort: