Examine source code of The Witcher

{
  "name": "The Witcher",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "rgba(4, 28, 41, 1)",
      "tab_background_text": "rgba(255, 255, 255, 1)",
      "toolbar": "rgba(84, 84, 84, 1)",
      "bookmark_text": "rgba(255, 255, 255, 1)",
      "toolbar_field": "rgba(232, 230, 250, 1)",
      "toolbar_field_text": "rgba(26, 0, 0, 1)",
      "tab_line": "rgba(240, 239, 178, 0.77)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{8df2331f-93af-4fe2-924b-90eac76cf2dd}"
    }
  }
}