Examine source code of Winter field

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Winter field",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.jpg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "right center"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(242, 195, 183, 0.64)",
      "toolbar_text": "rgb(8, 8, 8)",
      "frame": "rgb(15, 15, 15)",
      "tab_background_text": "rgb(255, 252, 250)",
      "toolbar_field": "rgb(255, 255, 255)",
      "toolbar_field_text": "rgb(6, 6, 6)",
      "tab_line": "rgb(225, 3, 48)",
      "popup": "rgb(255, 255, 255)",
      "popup_text": "rgb(0, 0, 0)",
      "tab_loading": "rgb(225, 3, 48)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{0a3cefb3-17a0-4a28-b2d2-e5a93b0fda5d}"
    }
  }
}