Examine source code of Frozen green

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Frozen green",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-036-40a272fe657f748396e017c7a64ee2dc.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(33, 38, 40, 0.18)",
      "toolbar_text": "rgb(247, 253, 251)",
      "frame": "rgb(46, 95, 109)",
      "tab_background_text": "rgb(255, 255, 255)",
      "toolbar_field": "rgb(86, 100, 100)",
      "toolbar_field_text": "rgb(255, 255, 255)",
      "tab_line": "rgb(117, 149, 161)",
      "popup": "rgb(255, 255, 255)",
      "popup_text": "rgb(90, 93, 154)",
      "tab_loading": "rgb(117, 149, 161)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{0a5502a6-3fcf-4821-a254-4cc587fe82f2}"
    }
  }
}