Examine source code of Colourful drops

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Colourful drops",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.jpg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "center center"
      ],
      "additional_backgrounds_tiling": [
        "no-repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(39, 39, 39)",
      "toolbar_text": "rgb(255, 255, 255)",
      "frame": "rgb(30, 21, 42)",
      "tab_background_text": "rgb(255, 246, 182)",
      "toolbar_field": "rgb(255, 255, 255)",
      "toolbar_field_text": "rgb(0, 0, 0)",
      "tab_line": "rgb(129, 255, 233)",
      "popup": "rgb(30, 21, 42)",
      "popup_text": "rgb(255, 141, 0)",
      "tab_loading": "rgb(129, 255, 233)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{0efb5424-aaea-4769-b2cd-e5657a4a804f}"
    }
  }
}