[Dark Mode] Improve visual contrast of the LinkLabel control in dark mode

[Zheng-Li01]

.NET version

9.0.0-rc.1.24414.1 + build private dll form winforms repo main branch

Did it work in .NET Framework?

No

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

This is a new feature Dark Mode: #11857

Issue description

The linklable control is not clear in the DarkMode

Steps to reproduce

1. Create a WinForms .NET Core application with LinkLable control.
2. Enable DarkMode by Application.SetColorMode(SystemColorMode.Dark) in Program.cs file.
3. Run the application.

[goldberger1441]

Are there any further plans on this issue ?
I think the main problem is, that plain windows settings are used and these does not fit together ? so it is probably also somehow related to the windows team - it currently reads data from "internet explorer" colors via regsistry?

Of course workarounds are possible by deriving from LinkLabel,
but if there is chance to get this fixed we would like to stay as close to "pure Winforms" as possible..

@KlausLoeffelmann , @Zheng-Li01 : What do you think of the following approach (only tested from outside, never built winforms itself): Use the code that is already there for high contrast (3 of 4 highcontrast templates are dark in my win11) and handle it exactly the same way:

 [SRCategory(nameof(SR.CatAppearance))]
 [SRDescription(nameof(SR.LinkLabelLinkColorDescr))]
 public Color LinkColor
 {
     get => _linkColor.IsEmpty
  <<       ? SystemInformation.HighContrast ? SystemColors.HotTrack : IELinkColor
  >>       ? SystemInformation.HighContrast||**SystemColorMode == SystemColorMode.Dark** ? SystemColors.HotTrack : IELinkColor
         : _linkColor;
     set
     {
         if (_linkColor != value)
         {
             _linkColor = value;
             InvalidateLink(null);
         }
     }
 }