Plasma5 Screen Orientation - Rotate 90 problems

When running Tumbleweed on bare metal using an AMD HD6850 graphics card and then rotate the monitor 90 degrees. Only the top 60 percent of the monitor is displaying the desktop the bottom 40 percent is black.

Also the portion of the desktop which does appear looks to be truncated as the bottom panel is missing.

Can someone running Tumbleweed please try to rotate your monitor 90 degrees to see if you can replicate the issues that i’m having. Perhaps it is only AMD / ATI video cards which are having this issue. I’m only running Tumbleweed on one computer so I can not test it with Nvidia or Intel video.

thanks