Class cannot be used with CSS transitions

[Glutnix]

I tried adding a background-color CSS Transition with no success - I believe this is because the class is being appended to the node, which is then being removed and appended into a fresh div, thus losing its transition state.

[leafo]

The element is the same but it's moved in the dom when sticking a float element. I think the move causes the transition to break. Not sure what the best solution is because moving the element makes the spacer implementation a lot simpler.

[Glutnix]

I haven't tried it but I assume you could delay changing the class on the element until it had been reattached to the document, thus give CSS transitions a before and after state to draw upon.