Examine source code of Seattle Mariners

{
  "theme": {
    "images": {
      "theme_frame": "MarinersHeaderJPG.jpg"
    },
    "colors": {
      "frame": "#171acf",
      "tab_background_text": "#09a16e"
    }
  },
  "version": "2.0",
  "name": "Seattle Mariners",
  "manifest_version": 2,
  "description": "Seattle Mariners Baseball Theme for Mozilla Firefox"
}