I found a solution for my suggestion in TC: Options > Layout: uncheck 'Windows XP theme background'. Win10/11 do not use the XP theming.The background color of the horizontal button bar is white (RGB 255,255,255) while the rest of the interface, even the vertical button bar, has the light gray color (clBtnFace; on Win10 this is RGB 240,240,240).
Please make the background color of the horizontal button bar also light gray (also for the drive buttons bar). It would give a more coherent interface. Thanks!
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Another request (nice to have):
In the dark mode most colors are adjustable by the user, perhaps this could also be made for the light mode? Like the colors for the horizontal lines etc. So the user could choose between the normal mode (Windows current/classic colors), light mode (user adjustable) and dark mode (user adjustable).