CSS3 transition (transform) not working in Firefox, but in Chrome and Safari

Question

I'm working on a simple slider, which uses CSS transitions to animate the slides. I created a pen with some basic styling and some javascript here. Note: Since Codepen uses Prefixfree I haven't used any prefixes.

The only part, which is animating is .slider__anim, not the .slider__item itself. I used position: absolute for all non active slides and position: relative for the active slide. That way I don't have to use a fixed height for my .slider.

In Chrome and Safari it works pretty well, but for some reason it just doesn't fire the CSS transitions in Firefox. Is this a bug in Firefox or is there any special markup for Firefox?

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Answer 1

For everybody, who has the same problem: It's a bug in Firefox, see: https://bugzilla.mozilla.org/show_bug.cgi?id=625289