Examine source code of Showerhead

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Soffione",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.png",
        "images/1.png"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "right top",
        "right top"
      ],
      "additional_backgrounds_tiling": [
        "repeat",
        "no-repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(218, 211, 218)",
      "toolbar_text": "rgb(0, 0, 0)",
      "frame": "rgb(255, 255, 255)",
      "tab_background_text": "rgb(0, 0, 0)",
      "toolbar_field": "rgb(255, 255, 255)",
      "toolbar_field_text": "rgb(142, 142, 142)",
      "tab_line": "rgb(0, 0, 57)",
      "popup": "rgb(243, 244, 247)",
      "popup_text": "rgb(8, 6, 8)",
      "tab_loading": "rgb(0, 0, 57)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{b7409ebd-d7e4-461f-b2c9-3cd6d2f6fad8}"
    }
  }
}