Examine source code of Gurple

{
  "name": "Gurple",
  "manifest_version": 2,
  "version": "3.0",
  "theme": {
    "images": {
      "theme_frame": "black.jpg"
    },
    "colors": {
      "frame": "rgba(33, 33, 33, 1)",
      "tab_background_text": "rgba(65, 30, 107, 1)",
      "toolbar": "rgba(33, 33, 33, 1)",
      "bookmark_text": "rgba(116, 56, 201, 1)",
      "toolbar_field": "rgba(0, 0, 0, 1)",
      "toolbar_field_text": "rgba(116, 56, 201, 1)",
      "tab_line": "rgba(116, 56, 201, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{465bbbe2-7183-49be-82ed-9fe1e9caa215}"
    }
  }
}