Why is IE 11 not rendering :after element, showing css as crossed out in dev tools?

Question

I have an angular app with two font icons in a given screen. These are rendered just fine in chrome, firefox and edge, but on IE 11 they do not display. The icons are to be

Answer 1

I had a similar issue, the after element on an tag wasn't rendered in IE11, though I could see the CSS style for it. Freddie's answer here solved the issue for me. Add this to the css display: block;