Hello,It seems that this issue is not with symbolic links but with relative symbolic links. Symlinking directly to the absolute path of the real file fixes the bug :
sylvain@bureau:/usr/share/xul-ext/ublock-origin/css/fonts$ ls -l total 12lrwxrwxrwx 1 root root 62 juil. 30 11:45 fontawesome-webfont.ttf -> /usr/share/fonts/truetype/font-awesome/fontawesome-webfont.ttf
-- Sylvain Terrien
