Examine source code of Purple Pixel City

{
  "name": "Purple Pixel City",
  "manifest_version": 2,
  "version": "2.0",
  "theme": {
    "images": {
      "theme_frame": "FirefoxBackground.png"
    },
    "colors": {
      "frame": "rgba(13, 3, 33, 1)",
      "tab_background_text": "rgba(138, 49, 194, 1)",
      "toolbar": "rgba(13, 6, 46, 0.8)",
      "bookmark_text": "rgba(232, 100, 184, 1)",
      "toolbar_field": "rgba(4, 0, 5, 1)",
      "toolbar_field_text": "rgba(232, 100, 184, 1)",
      "tab_line": "rgba(255, 255, 255, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{ea80fdad-9154-4981-b278-080d0c06e88c}"
    }
  }
}