https://www.mozilla.org/firefox/59.0/system-requirements/ Firefox requires Pango 1.'''14''' or higher. Do you have those packages installed in package manager Did you do as error suggest to add the directory containing the pango packages. While this forum is for pretty much all Firefox related things we generally do not really help with building Firefox. If you like you could also post in http://forums.mozillazine.org/viewforum.php?f=42 - Third Party/Unofficial Builds as somebody may be able to help you there.