Hi, I installed v2.6.38 and now various graphic parts on my screen are randomly flickering and disappearing and reappearing, making it difficult to work.  Has anyone else experienced this?   And if so, is there a fix?  Maybe a graphic card setting?  It never did this on any previous version.  Attached is a video clip.  I've since had to revert back to v2.1 (the most recent version on the history site).