Examine source code of Custom peaceful forest

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Custom peaceful forest",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.jpg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "left top"
      ],
      "additional_backgrounds_tiling": [
        "no-repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(223, 246, 223)",
      "toolbar_text": "rgb(116, 196, 32)",
      "frame": "rgb(79, 133, 31)",
      "tab_background_text": "rgb(255, 255, 255)",
      "toolbar_field": "rgb(255, 255, 236)",
      "toolbar_field_text": "rgb(224, 224, 141)",
      "tab_line": "rgb(135, 235, 49)",
      "popup": "rgb(133, 242, 113)",
      "popup_text": "rgb(205, 73, 40)",
      "tab_loading": "rgb(135, 235, 49)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{8af1b7fe-e42e-446b-b0a7-296b0136e665}"
    }
  }
}