Quickly scrolling between `n` values breaks animation

[mara-kr]

To replicate, hold the n slider and move from 2->8->2->8. I don't see the upper left quadrant of dots.

[HelloKayT]

This is a really weird visual bug. I looked into cancelling animation, and it's supposed to do it automatically when you start a new transition. Strangely, it seems to be an opacity problem. If you try to mouse over spots where you think they'll be, they'll magically pop in