Emoji-Support🎉🥳 for Fira Code on Linux: Add this to your fontconfig (~/.config/fontconfig.conf) (Tested with Konsole on Arch Linux and Ubuntu 18.04)

fonts.conf

<fontconfig>
...
    <match target="pattern">                                                    
        <test qual="any" name="family"><string>monospace</string></test>        
        <edit name="family" mode="assign" binding="same"><string>Iosevka Custom</string></edit>
        <edit name="family" mode="append" binding="weak"><string>JoyPixels</string></edit>
    </match>  
...
</fontconfig>