Thank you for taking the time to answer my questions!
It is still a bit unclear to me though.
You say that the default setting (the one that only allows integer scaling) at 200% draws everything twice as large. As I can see that the image is still sharp and clear at this scale, somehow each application is providing twice the number of pixels that it would do on a LoDPI screen. Is this correct? My question is then, how does the XWayland application (and the native Wayland app for that matter) know that it is supposed to do that? Does this still leave HiDPI-unaware applications looking small or will the compositor notice this and scale them to blurry normal size?
If all of the above is the case, I cannot understand why the same cannot be achieved for the fractional scaling. I have been reading a lot of issue threads on XWayland gitlab and similar, and the problem they often pose is that a global scaling factor for all XWayland windows would not be good as some might be HiDPI-aware and some might not. I assumed that this was also GNOME’s stance on the matter. However, it seems that in the integer scaling case, this is also the case and is seemingly “OK”?
My point being, if we are somehow able to draw XWayland application sharp and clear at 200%, 300%, 400% using integer scaling, why can’t we let the XWayland clients use the increased buffer size when doing the integer scaling step for fractional scaling?