Enabling XRender composite mode gives tearing video playback problem. "UnredirectFullscreen=true" in [Compositing] section of ~/.kde/share/config/kwinrc solves problem, but only for fullscreen playback. Disabling composing completly solves problem, but it not suitable. In testing I use xv video output, because x11 and gl output methods have bad performance at all. Also, why I ask about this problem here: https://bugs.kde.org/show_bug.cgi?id=229990
XRender not provide sync information - not nouveau bug.
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