> sharp edges takes indeed a little bit more cognitive visible effort
I have my doubts about this. It is 100% fad IMO.
And how Windows 11 lists rounded windows and corners as a "signature feature"!
https://docs.microsoft.com/en-us/windows/apps/design/signatu...
That's at least a decade after the W3C had a well-developed concept of relative units for use with the CSS:
https://www.w3.org/Style/Examples/007/units.html#future (2010)
Thus, with a sufficiently high DPI display, you're going to miss out on one of Windows 11's "signature experiences" and end up with "legacy" squarish corners instead.
> Because of how the scaling system works, when you design your UWP app, you're designing in effective pixels, not actual physical pixels. Effective pixels (epx) are a virtual unit of measurement, and they're used to express layout dimensions and spacing, independent of screen density. (In our guidelines, epx, ep, and px are used interchangeably.)
https://docs.microsoft.com/en-us/windows/apps/design/layout/...
Also, Windows scales the pixel size when you use a legacy application (non DPI aware) on high DPI displays.
This article quotes a researcher on this topic:
> A rectangle with sharp edges takes indeed a little bit more cognitive visible effort than for example an ellipse of the same size. Our ‘fovea-eye’ is even faster in recording a circle. Edges involve additional neuronal image tools. The process is therefore slowed down.¹
1: https://designmodo.com/rounded-corners/