Thanks for bumping this, with FontAwesome 5 the technique in the OP will no longer work. Our FA5 implementation switches from using an icon font to SVGs, so the content: "\f0a1" will no longer display an icon, the font where that character points will no longer be included.
Here is a way to do the same thing with SVGs once FA5 is in core:
@import "common/foundation/mixins";
[data-tag-name="tag1"]:link,
[data-tag-name="tag1"]:visited,
[data-tag-name="tag1"].bullet:before {
color: red;
}
[data-tag-name="tag1"].bullet:before {
background: transparent;
content: svg-uri('<svg fill="red" xmlns="http://www.w3.org/2000/svg" width="8px" height="8px" viewBox="0 0 512 512"><path d="M216 0h80c13.3 0 24 10.7 24 24v168h87.7c17.8 0 26.7 21.5 14.1 34.1L269.7 378.3c-7.5 7.5-19.8 7.5-27.3 0L90.1 226.1c-12.6-12.6-3.7-34.1 14.1-34.1H192V24c0-13.3 10.7-24 24-24zm296 376v112c0 13.3-10.7 24-24 24H24c-13.3 0-24-10.7-24-24V376c0-13.3 10.7-24 24-24h146.7l49 49c20.1 20.1 52.5 20.1 72.6 0l49-49H488c13.3 0 24 10.7 24 24zm-124 88c0-11-9-20-20-20s-20 9-20 20 9 20 20 20 20-9 20-20zm64 0c0-11-9-20-20-20s-20 9-20 20 9 20 20 20 20-9 20-20z"></path></svg>');
vertical-align:baseline;
}
A few notes about this:
/// Helper function to easily use an SVG inline in CSS
/// without encoding it to base64, saving bytes.
/// It also helps with browser support, especially for IE11.
///
/// @author Jakob Eriksen
/// @link http://codepen.io/jakob-e/pen/doMoML
/// @param {String} $svg - SVG image to encode
/// @return {String} - Encoded SVG data uri
@function svg-uri($svg) {
$encoded: "";
$slice: 2000;
$index: 0;
$loops: ceil(str-length($svg) / $slice);
@for $i from 1 through $loops {
$chunk: str-slice($svg, $index, $index + $slice - 1);
$chunk: str-replace($chunk, '"', "'");
$chunk: str-replace($chunk, "<", "%3C");
$chunk: str-replace($chunk, ">", "%3E");
$chunk: str-replace($chunk, "&", "%26");
$chunk: str-replace($chunk, "#", "%23");
$encoded: #{$encoded}#{$chunk};
$index: $index + $slice;
}
@return url("data:image/svg+xml;charset=utf8,#{$encoded}");
}
/// Replace `$search` with `$replace` in `$string`
/// @author Hugo Giraudel
/// @link http://sassmeister.com/gist/1b4f2da5527830088e4d
/// @param {String} $string - Initial string
/// @param {String} $search - Substring to replace
/// @param {String} $replace ('') - New value
/// @return {String} - Updated string
@function str-replace($string, $search, $replace: "") {
$index: str-index($string, $search);
@if $index {
@return str-slice($string, 1, $index - 1) + $replace +
str-replace(
str-slice($string, $index + str-length($search)),
$search,
$replace
);
}
@return $string;
}
[data-tag-name="tag1"]:link,
[data-tag-name="tag1"]:visited,
[data-tag-name="tag1"].bullet:before {
color: red;
}
[data-tag-name="tag1"].bullet:before {
background: transparent;
content: svg-uri('<svg fill="currentColor" xmlns="http://www.w3.org/2000/svg" width="8px" height="8px" viewBox="0 0 512 512"><path d="M216 0h80c13.3 0 24 10.7 24 24v168h87.7c17.8 0 26.7 21.5 14.1 34.1L269.7 378.3c-7.5 7.5-19.8 7.5-27.3 0L90.1 226.1c-12.6-12.6-3.7-34.1 14.1-34.1H192V24c0-13.3 10.7-24 24-24zm296 376v112c0 13.3-10.7 24-24 24H24c-13.3 0-24-10.7-24-24V376c0-13.3 10.7-24 24-24h146.7l49 49c20.1 20.1 52.5 20.1 72.6 0l49-49H488c13.3 0 24 10.7 24 24zm-124 88c0-11-9-20-20-20s-20 9-20 20 9 20 20 20 20-9 20-20zm64 0c0-11-9-20-20-20s-20 9-20 20 9 20 20 20 20-9 20-20z"></path></svg>');
vertical-align:baseline;
}
This is not an ideal solution, it makes the CSS less readable. But on the other hand, it’s efficient (no additional requests) and independent (the whole icon is in the SVG path).
The easiest way to do this is to use the new theme component: Tag Icons
