Strategy for cancelling running css transition is incorrect and doesn't work in Firefox

[Narretz]

When we cancel a css transition-based animation, we do not explicitly set the transition-property property to none, but instead we remove the animation classes, and assume that this will immediately stop the animation. However, this behavior is not supported in Firefox and IE11, because it's not actually to spec: https://bugzilla.mozilla.org/show_bug.cgi?id=1425014#c6