Since the upgrade to plasma 5.7.2 (from 5.6.5) all icons in qt (4 and 5) applications are too small on my hidpi-screen. For things belonging directly to plasma (for example the desktop context menu) this was also the case for plasma 5.6. But with plasma 5.7.2 the icons of all qt(4,5) applications like dolphin, okular, yakuake, spectacle are too small as well. It seems that the hidpi-scaling only works for fonts and not for icons any more. Note, changing qt's scaling only seem to influence the font size, but not icon sizes. I will attach a screenshot. Reproducible: Always
Created attachment 100337 [details] screenshot of small icon situation
Okay, I see the problem now. In 5.6. I had to set QT_AUTO_SCREEN_SCALE_FACTOR=1 in /etc/profile.d since the plasma-internal scaling options did not work any more (coming from 5.5). It seems plasma overrides this option now and relies again on the scaling options one can set in systemsettings. So it works again. Sorry for the noise.