Examine source code of FreeGary

{
  "theme": {
    "images": {
      "theme_frame": "FreeGary-Header.jpg"
    },
    "colors": {
      "frame": "#757575",
      "tab_background_text": "#000000"
    }
  },
  "version": "2.0",
  "name": "FreeGary",
  "manifest_version": 2,
  "description": "A Persona to raise awareness and to help and show that you support the campaign to have a fair future for Gary McKinnon - All twitters are there only some are cut off in the preview, the larger your monitor the more you can see!"
}