This contour trace blows up on zoom

[cpsievert]

The x/y limits are fine, but the coloring breaks on any zoom event, perhaps a rounding issue?

http://codepen.io/cpsievert/pen/qNEXKV

[jackparmer]

I'm seeing the same issue with these contour traces by @empet

https://plot.ly/dashboard/jackp:16964/present