Not that it's very important, but shouldn't the preview of open windows also fit its horizontal window sizes?
Sorry but I'm just trying to figure out what you mean. With the screenshots you attached, aren't the preview windows already dynamically changing slightly based on the shape of the window that's being previewed? Or maybe I'm misunderstanding what you're specifically meaning.
I played a bit and I have the Impression that the Window Preview depends on the Shape of the open Window. Your ''Informazioni'' Window has a small Shape and that You get in the Preview.
@applecheeks37, yes, but as you can see only vertically, not also horizontally. In the first screenshot it fits all sides, while in the second one it doesn't fit the top and bottom edges. @Ponce-De-Leon, yes, as it should do, but why shouldn't it also fit the top and bottom edges perfectly precisely? I have the impression that there's some detail that I'm missing 
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I see what you're saying now. I presume that's because at a certain width it just assumes the window would be more or less a 16 by 9 window. I would think this would be a good feedback option that they could take a look at and possibly integrate? Although that fix may or may not be an annoying fix, who knows what else is using that.
I think that is because of this black Background. The Window itself lays on this Background. So, the Background is not a Part of the Window. The Window is on this Background and has this Title at the Top.
@applecheeks37, it's a default setting so many might still be using it, it's certainly a nice and useful feature, but to me pointing the icon to show the window would be better than waiting for the preview window to point 
. @Ponce-De-Leon, pretty confusing 
. Looks like you mean that background and window react differently to each other .
Not directly differently ... for me it is more like a ... how can I say that ... It looks for me like a 2-Layer-Process wher the Background tries to fit but not entirely can.
If you are using the Zorin taskbar, You can adjust it a bit in the Settings. But there is not too much. Go to the Taskbar Settings, there to the Behavior Tab and there to Hover:
See to the red marked Area. Click on the Gear Icon.
Agree, this is how I'd have explained it.
It's right from there that I started, I set the minimum (100) and it still don't always fit the real window size. At this point (and after thinking a bit more 
) my only and simplest explanation is that the value refers to the minimum preview window size in vertical, so despite the window of the software is smaller the preview of that window stays at the chosen value.
