ID:1970963
 
Resolved
Regression in 509.1309: Flicks did not appear on some atoms until a glide or other appearance change on the atom, at which point the flick would appear in-progress and continue normally.
BYOND Version:509.1309
Operating System:Windows 7 Ultimate 64-bit
Web Browser:Chrome 46.0.2490.71
Applies to:Webclient
Status: Resolved (509.1310)

This issue has been resolved.
Descriptive Problem Summary:

flick() will actually not show its animation until the source atom has moved. If the atom remains still for the duration of the icon state's animation, then nothing will display at all.

This seems related to id:1856412.
Lummox JR resolved issue with message:
Regression in 509.1309: Flicks did not appear on some atoms until a glide or other appearance change on the atom, at which point the flick would appear in-progress and continue normally.
Found it. This was due to one of the changes I made to improve FPS, but I missed one spot.