Frozen Aura sleep VFX disappears

[Erinyx]

In what I suspect might be a bug related to i27.3, but can't say for sure because my recent Ice Stalker wasn't high enough to use the power before the patch hit, I've noticed that when I hit Frozen Aura, the little "trapped in ice" animation that indicates the Sleep effect is active disappears after the first couple of seconds, rather than lasting the entire time the enemies are afflicted.  Some of them maintain the wriggling animation throughout, some don't even do that, but just sort of hold still.  This makes it tricky to tell when the effect wears off, though.