The time slider does not snap to ticks consistently. I have not found a way to reproduce the problem consistently, but something this simple seems to work about 50% of the time.
Reproduction steps
Move time slider to frame 16 (1 second)
Draw a single stroke.
Move the time slider back and forth. It should jump two frames at a time (to frame 18 or 14), but it sometimes jumps only one frame.
The time slider does not snap to ticks consistently. I have not found a way to reproduce the problem consistently, but something this simple seems to work about 50% of the time.
Reproduction steps