IE: Child element loses animation when parent is temporary hidden - css

Question

After hide and show of the parent element, the child element no longer rotates(loses it css3 animation).
Removing parent element animation and doing hide/show won't cause the same issue(The issue only occurs when the parent element also have an animation)
I was testing in IE 11.
Is this a known issue?
Here is the snippet in codepen(copied below) http://codepen.io/agirma/pen/byIEd
/*-------- CSS start ---------*/
#-webkit-keyframes show_content {
from {
-webkit-transform: scale(0);
opacity:0;
transform: scale(0);
opacity:0;
}
to {
-webkit-transform: scale(1);
opacity:1;
transform: scale(1);
opacity:1;
}
}
#keyframes show_content {
from {
-webkit-transform: scale(0);
opacity:0;
transform: scale(0);
opacity:0;
}
to {
-webkit-transform: scale(1);
opacity:1;
transform: scale(1);
opacity:1;
}
}
#-webkit-keyframes rotate_content {
from {
-webkit-transform: rotate(0deg);
transform: rotate(0deg);
}
to {
-webkit-transform: rotate(360deg);
transform: rotate(360deg);
}
}
#keyframes rotate_content {
from {
-webkit-transform: rotate(0deg);
transform: rotate(0deg);
}
to {
-webkit-transform: rotate(360deg);
transform: rotate(360deg);
}
}
#parent {
display:block;
background:gray;
width: 100px;
height: 100px;
padding: 20px;
-webkit-animation: show_content 4s;
-ms-animation: show_content 4s;
amimation: show_content 4s;
}
#child {
display:block;
width:80px;
height: 80px;
border:solid 1px red;
-webkit-animation: rotate_content 1s linear infinite;
-ms-animation: rotate_content 1s linear infinite;
amimation: rotate_content 1s linear infinite;
}
/*------------CSS end----------*/
<div id="parent">
<div id="child"></div>
</div>
<button onclick="toggleVisibility()">toggle display</button>
<script>
function toggleVisibility() {
var div = document.getElementById('parent');
div.style.display = div.style.display == 'none' ? 'block' : 'none';
}
</script>

Answer 1

I don't believe this issue is "known". I found it myself a couple of weeks ago when IE-testing a webapp I'm building. I finally got around to looking at it today, and upon noticing the same conditions for occurrence that you've listed, I decided to submit a bug report for IE. I was just about to do that when I found this question.
My bug report:
https://connect.microsoft.com/IE/feedbackdetail/view/941104/ie-11-bug-with-nested-css-animations-upon-display-of-previously-hidden-parent
Update:
The bug was successfully reproduced by Microsoft engineers and will be investigated.