Examine source code of Mac Reunification

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#cacaca",
      "tab_background_text": "#000000"
    }
  },
  "version": "2.0",
  "name": "Mac Reunification",
  "manifest_version": 2,
  "description": "For use with addons that move the tabs to the side or bottom, for example Tree Style Tab. Brings back the \"unified toolbar\" look of OS X in Firefox 29+"
}