.NET version
.NET SDK 10.0.100.rc.2.25419.103
Did it work in .NET Framework?
No
Did it work in any of the earlier releases of .NET Core or .NET 5+?
The issue also can reproduce on .NET SDK 10.0 Prevview7. there has the known issue #13720 to track. after the fix of PR #13809, the issue has been fixed when the FlatStyle is Flat/Popup, but still reproduce when the FaltStyle is Standard
Issue description
The BackgroundImage of Button is not displayed when the FlatStyle is Standard in DrakMode
.NET 10.0 rc.2 & rc.1 results:

.NET 10.0 preview7 results:

.NET 9.0 results:

Steps to reproduce
- Create a winforms app, a form and a button with a background image.
- Run the project in DarkMode
- Observe results