https://bugs.freedesktop.org/show_bug.cgi?id=103791
--- Comment #17 from Michel Dänzer michel@daenzer.net --- Thanks. I think I see what's happening, but I need some time to think about how to address it.
Meanwhile, you should be able to re-enable TearFree by forcing a modeset, e.g. by re-enabling the TearFree property:
xrandr --output DisplayPort-0 --set TearFree on