there's a 1px gap under CDockAreaTitleBar, and cannot be themed. #791
Description
I'm writting stylesheet to QtAds, but I find there's a 1-px gap under CDockAreaTitleBar, which donnot response to any qss code.
If one screenshot the app, and magnify it, and will see it. here's a light theme. note the position where arrow points.
and in dark mode , it's even more obvious, since its color is #FFFFFFF, so it's very annoying.
how to fix it ? I guess there may be some error when computation CDockAreaTitleBar's size.