Just one week after the last xf86-video-intel DDX update, Chris released the xf86-video-intel 2.21.9 driver this morning. "Consolidating the copy-on-write support, hopefully cleaning up the last of the regressions."
This new Intel X.Org driver release hopefully restores v-sync on textured videos, fixes a performance regression from not promoting large fills to the GPU, undoing a pixmap clone before doing a DRI2 copy region call, and fixing the ordering of possible clones. A performance regression found within my recent SNA vs. UXA benchmarks has also been taken care of.
There's 25 changes to this updated driver. More details can be found in the release announcement.