Created attachment 108522 [details] Screenshot showing garbled fonts rendering Since the upgrade to Kubuntu Artful, using Plasma 5.11.1 via backports konsole has a font rendering bug as can be seen in the attachment. Accessing the terminal forces some repaint which resolves the problem, so not a real showstopper, but quite an annoyance nevertheless.
I think this was caused by native intel driver Tearing prevention. I've disabled that in Xorg conf and have not seen the problem since!