Examine source code of Echidna

{
  "manifest_version": 2,
  "version": "0.2",
  "name": "Echidna",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.png"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "right center"
      ],
      "additional_backgrounds_tiling": [
        "no-repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(245, 8, 8, 0)",
      "toolbar_text": "rgb(255, 255, 255)",
      "toolbar_top_separator": "rgba(0, 0, 0, 0)",
      "frame": "rgb(42, 42, 46)",
      "tab_text": "rgb(255, 255, 255)",
      "tab_background_text": "rgb(50, 50, 50)",
      "toolbar_field": "rgba(255, 255, 255, 1)",
      "toolbar_field_text": "rgb(50, 50, 50)",
      "toolbar_field_border_focus": "rgb(190, 190, 190)",
      "tab_line": "rgb(21, 59, 254)",
      "popup": "rgb(231, 242, 244)",
      "popup_text": "rgb(84, 84, 84)",
      "ntp_background": "rgb(249, 249, 250)",
      "ntp_text": "rgb(0, 0, 0)",
      "tab_loading": "rgb(255, 255, 255)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{d108fe9c-bf8a-49a0-8d94-10c5a598b580}"
    }
  }
}