Until january 13th it rendered perfect. Crisp and clean but after an apt upgrade the issue appeared.
I tried to tweak the settings but no one brings back the rendering quality I had just three days ago. I always get rainbow-colored borders.
The problem is I can't find the responsible package to try to downgrade it... or open a bug report against it. A web search for recent kde bugs or problems didn't show anything.
It is quite unconfortable to work with a multicolored font everywhere but I don't know what to do now.
Please if someone else noticed the problem please advice