Which mount animations and on what mounts? I assume you’re talking about Dragonriding mounts randomly using the MountExtraWide animations again. Really wish they would fix those animations already. I don’t think it’s necessary for the leg spread to be so wide, especially since they don’t do such a wide leg spread on Worgen last time I checked. It also causes noticeable model distortion on every race where the leg spread is significantly wider with MountExtraWide than MountWide.
Just about every weekly reset and/or hotfix randomly changes what animations are being used on the Dragonriding mounts.