https://bugs.freedesktop.org/show_bug.cgi?id=106490
--- Comment #6 from Tomáš Chvátal tomas.chvatal@gmail.com --- This might be possible duplicate of: https://bugs.freedesktop.org/show_bug.cgi?id=104597
I can reproduce this too on openSUSE with Mesa 18.1. The issue itself is exposed only on Radeon driver not on intel/nouveau.
The workaround of course works, but I think there must be some bug in Mesa radeonsi code as the intel/nouveau both manage to play stuff properly using the libva and the conversion to opengl.