I did a recent update, 27 April and don't think i noticed until today, the artifacts you described as well as my characters in general are missing noticeable number of pixels when using Forum.
I did remember this thread and have just added the option under devices. Well I have re-booted and the problem is still there. I will leave it for the time being and may roll back my system later as the foont is smearing or something.Edit:
Ooops, found another update and since it looked like updaing something graphics I updated and re-booted, and now I can not repeat the the video intrusion in the konsole window. Most interesting and welcome too.
Do you really have and etc/X110/.... if not can you be persuaded to modify so a poor beginner like me don't start thinking he is missing out on some goodies