First, thanks to @Jpsy as my answer is based on that.
I have extended that answer to support the Google Material Icons pack as the custom icon.
<link href="https://fonts.googleapis.com/icon?family=Material+Icons" rel="stylesheet">
<ul>
<li>Curabitur non nulla sit amet nisl tempus convallis quis ac lectus. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Donec velit neque, auctor sit amet aliquam vel, ullamcorper sit amet ligula. Pellentesque in ipsum id orci porta dapibus.</li>
<li>Nulla porttitor accumsan tincidunt. Mauris blandit aliquet elit, eget tincidunt nibh pulvinar a. Aliquet quam id dui posuere blandit. Curabitur non nulla sit amet nisl tempus convallis quis ac lectus.</li>
</ul>
ul {
position: relative;
list-style: none;
margin-left: 0;
padding-left: 1.2em;
}
ul li:before {
font-family: 'Material Icons';
content: "double_arrow"; /* Change this to whichever icon you would like from https://fonts.google.com/icons?selected=Material+Icons */
position: absolute;
left: 0;
}
@font-face {
font-family: 'Material Icons';
font-style: normal;
font-weight: 400;
src: url(https://example.com/MaterialIcons-Regular.eot); /* For IE6-8 */
src: local('Material Icons'),
local('MaterialIcons-Regular'),
url(https://example.com/MaterialIcons-Regular.woff2) format('woff2'),
url(https://example.com/MaterialIcons-Regular.woff) format('woff'),
url(https://example.com/MaterialIcons-Regular.ttf) format('truetype');
}