Oh, that. Don’t worry about it. It’s the game’s anti-debug, it makes using waitable swapchains very unreliable.
All Ubisoft games have this problem, until they pull their head out of their butt and stop doing this stuff.
Use this version of Special K to defeat some of the performance problems with this feature in Ubisoft games:
SpecialK64_UbisoftSucks.7z (7.6 MB)