CSS transitions not working on Epiphany

Question

I have a very simple scenario. Is the following (taken from here):

.box {
  border-style: solid;
  border-width: 1px;
  display: block;
  width: 100px;
  height: 100px;
  background-color: #0000FF;
  -webkit-transition: width 2s, height 2s, background-color 2s, -webkit-transform 2s;
  transition: width 2s, height 2s, background-color 2s, transform 2s;
}

.box:hover {
  background-color: #FFCCCC;
  width: 200px;
  height: 200px;
  -webkit-transform: rotate(180deg);
  transform: rotate(180deg);
}

<div class="box"></div>

On Firefox and Opera it works without problems. But on Epiphany (running on Raspbian) the transition simply doesn't run. The element goes from the initial state to the final state without passing through the transition.

To say the truth, it only begins to work several seconds after the page load. It appears that there's some weird trigger that is fired at some moment, and then the transition start to work. The same goes for animations.

So, is there some undocumented trick (or bug) here? Because I've spent many hours on this, searched everywhere and couldn't find an answer.

Thanks for the support!