IDEA 15: Either redraw problems or terrible font Follow

I am getting mad trying to solve this.
On my Kubuntu 15 I either

• use JDK 7, have font rendering that is ok, but have redraw problems in all popups
• use JDK 8, have terrible font rendering, but popups work fine

See screenshots:


So I am in between a rock and a hard place.

Any way out?