Examine source code of Riders Club

{
  "manifest_version": 2,
  "version": "4",
  "name": "ridersclub",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.jpg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "right top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(13, 12, 12, 0.37)",
      "toolbar_text": "rgb(255, 255, 255)",
      "frame": "rgb(154, 155, 155)",
      "tab_background_text": "rgb(255, 255, 255)",
      "toolbar_field": "rgba(42, 79, 69, 0.74)",
      "toolbar_field_text": "rgb(255, 255, 255)",
      "tab_line": "rgb(255, 255, 255)",
      "popup": "rgb(54, 82, 90)",
      "popup_text": "rgb(255, 255, 255)",
      "button_background_active": "rgb(14, 14, 14)",
      "button_background_hover": "rgb(17, 94, 116)",
      "frame_inactive": "rgb(248, 243, 243)",
      "ntp_background": "rgb(115, 116, 117)",
      "popup_border": "rgb(146, 145, 143)",
      "popup_highlight_text": "rgb(85, 72, 72)",
      "popup_highlight": "rgb(143, 143, 143)",
      "sidebar_border": "rgb(154, 153, 152)",
      "sidebar_highlight_text": "rgb(245, 245, 245)",
      "sidebar_highlight": "rgb(145, 136, 76)",
      "sidebar_text": "rgb(255, 255, 255)",
      "sidebar": "rgb(54, 82, 90)",
      "tab_background_separator": "rgb(255, 255, 255)",
      "tab_loading": "rgb(70, 140, 132)",
      "tab_selected": "rgba(17, 94, 116, 0.71)",
      "tab_text": "rgb(255, 255, 255)",
      "toolbar_field_border_focus": "rgb(0, 0, 0)",
      "toolbar_field_border": "rgb(255, 255, 255)",
      "toolbar_field_focus": "rgb(70, 140, 113)",
      "toolbar_field_highlight_text": "rgb(255, 255, 255)",
      "toolbar_field_highlight": "rgb(79, 106, 135)",
      "toolbar_field_separator": "rgb(255, 255, 255)",
      "toolbar_field_text_focus": "rgb(0, 0, 0)",
      "toolbar_top_separator": "rgba(255, 255, 255, 0)",
      "toolbar_vertical_separator": "rgb(255, 255, 255)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{521a4dc4-38f4-44fb-aa56-41385ac7e8fc}"
    }
  }
}