Comment # 61 on bug 1199020 from Stefan Hundhammer

So AFAICS while using a nice dpi value that can be divided by 48 probably
prevents drawing artifacts for rendering fonts, at the same time scaling it up
to 200% is way over the top.

Desktop scaling factors e.g. in KDE Plasma use multiples of 25%, i.e. 100%,
125%, 150%, 200%; and that seems to work quite well. I don't see a reason why
that shouldn't work for our YaST installer.

So we should make Qt not enforce such rigid scaling factors and rather stick
with what we tell it with the Xft.dpi X resource; that's already rounded well
enough.

I'll try different scale factor rounding policies; that seems to be the root of
the problem here.