Add Emoji to Linux Fontconfig

57-add-emoji-support.conf

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE fontconfig SYSTEM "fonts.dtd">
<!--
EmojiOne Color SVGinOT Font

Author: Santiago Saavedra <ssaavedra@gpul.org>
License: CC0
Year: 2016

Install:
  Copy to $XDG_CONFIG_DIR/fontconfig/conf.d/57-add-emoji-support.conf
  Run fc-cache -f

Description:
  This fontconfig script prepends an emoji family to every other family.
  Then, the emoji family is defined to have EmojiOne Color as its default member.
  This would work with a build of Noto Color Emoji which wouldn't override
  non-emoji symbols, but the one I have overrides at least numbers.

-->
<fontconfig>
  <match>
    <!-- If the requested font is serif -->
    <test qual="any" name="family">
        <string>serif</string>
    </test>
    <edit name="family" mode="prepend_first">
      <string>emoji</string>
    </edit>
  </match>

  <match target="pattern">
    <!-- If the requested font is sans-serif -->
    <test qual="any" name="family">
        <string>sans-serif</string>
    </test>
    <!-- Followed by EmojiOne Color -->
    <edit name="family" mode="prepend_first">
      <string>emoji</string>
    </edit>
  </match>

  <match target="font">
    <!-- If the requested font is Bitstream Vera Sans Mono -->
    <test name="family" compare="eq">
        <string>Bitstream Vera Sans Mono</string>
    </test>
    <!-- Assign the monospace family last -->
    <edit name="family" mode="append_last">
      <string>monospace</string>
    </edit>
  </match>

  <!-- Add emoji generic family -->
  <alias binding="strong">
    <family>emoji</family>
    <!--
	<default><family>Noto Color Emoji</family></default>
    -->
    <default><family>EmojiOne Color</family></default>
  </alias>

  <!-- Alias requests for the other emoji fonts
  <alias binding="strong">
    <family>Apple Color Emoji</family>
    <prefer><family>EmojiOne Color</family></prefer>
    <default><family>sans-serif</family></default>
  </alias>
  <alias binding="strong">
    <family>Segoe UI Emoji</family>
    <prefer><family>EmojiOne Color</family></prefer>
    <default><family>sans-serif</family></default>
  </alias>
  <alias binding="strong">
    <family>Noto Color Emoji</family>
    <prefer><family>EmojiOne Color</family></prefer>
    <default><family>sans-serif</family></default>
    </alias>
  -->
</fontconfig>