https://github.com/nptr/msstyleEditor

You can open C:\Windows\Resources\Themes\aero\aero.msstyles and notice there are a lot of "DarkMode_Xxx" classes e.g. there is "DarkMode_CFD:ComboBox" on my Win11.

Try using SetWindowTheme combobox.hWnd, StrPtr("CFD") for ComboBoxes and probably a separate call for the dropdown scollbars will be needed.

cheers,
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