anchor.diff:        "text/html"
         "text/xml"
         "application/xhtml+xml"
  +      "application/vnd.mozilla.xul+xml"
         "x-scheme-handler/http"
         "x-scheme-handler/https"
         "x-scheme-handler/ftp"
  -      "x-scheme-handler/mailto"
  -      "x-scheme-handler/webcal"
  -      "x-scheme-handler/about"
  -      "x-scheme-handler/unknown"
       ];
     };
   
  
positive.code:   desktopItem = makeDesktopItem {
      name = browserName;
      exec = browserName + " %U";
      icon = icon;
      comment = "";
      desktopName = desktopName;
      genericName = "Web Browser";
  
negative.code:     ''
      }
  
      mkdir -p $out/share/icons
      ln -s "$out/lib/firefox-35.0.1/browser/icons/mozicon128.png" "$out/share/icons/firefox.png"
  
      mkdir -p $out/share/applications
      cp $desktopItem/share/applications/* $out/share/applications
  
  