Okay, many thanks.
Well, frankly, by now I have spent a lot of time trying all styles, see how they look like when using applications
(incl. file open/save, scrolling, selecting files and see how they are marked, etc.) trying to figure out how to adjust them.
Tried Skinstudio, went through many examples on the Wincustomize website.
Made an awful lot of screenshot, whilst comparing each style, and so on and so on.
In the end, I returned to the default style though.
In fact, I was reverted to WindowBlinds, merely because I was seeking a way to add some color to the all white titlebar:
in case of a few windows open, it sometimes is a bit difficult to see which titlebar one is grabbing, to move or close that window.
There is only a very thin line around the active window, at least that's the way I have it. My desktop is not entirely default, I changed
the desktop and also the taskbar color - although, that was way back at the introduction of Windows 10, i.e. I would need to
figure out again how I did it 
All provided skins within WindowBlinds, with all due respect, they all look very nice, but, well, they have something I don't like
(admittedly, it is all a personal taste of course).
Either to dark resulting in unable to see the name of the file in the titlebar because it is black font on very dark grey, or
selected files (Explorer, right window panel) were/are not 'greyed' or colored in any color, but are just getting a thin border, or
the sliders in scrollbars almost have the same color as the scrollbars themselves and therefor difficult to see then, or
the windows file open/file save dialog - is too darkgrey.
That aside, I'd like the windows not to have a 'shadow' because I very often capture screenshots using SnagIt and SnagIt
will take a wide border around the windowpanels, i.e. I have to manually select exactly what to capture.
That is not the case with windows without shadow, like 'Precision' or 'Modern'.
Is there a way to copy-save the default style so I may -try- to adjust the titlebar, if at all possible..
A bit like the below.
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