Hello,
Some apps have graphical glitches with fractional scaling. Please see:
https://bugs.kde.org/show_bug.cgi?id=464069
https://bugs.kde.org/show_bug.cgi?id=475886
Especially the screenshots:
bugsfiles.kde[.]org/attachment.cgi?id=162458
bugsfiles.kde[.]org/attachment.cgi?id=162462
I’m willing to contribute $100 for those issues to be resolved in the upcoming KDE 6 release.