Examine source code of Eerie

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Eerie",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.jpg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "left top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(62, 63, 64, 0.57)",
      "toolbar_text": "rgb(255, 255, 255)",
      "frame": "rgb(70, 70, 78)",
      "tab_background_text": "rgb(255, 255, 255)",
      "toolbar_field": "rgba(98, 100, 102, 0.39)",
      "toolbar_field_text": "rgb(242, 242, 242)",
      "tab_line": "rgb(104, 85, 86)",
      "popup": "rgba(33, 33, 36, 0.72)",
      "popup_text": "rgb(248, 249, 252)",
      "tab_loading": "rgb(104, 85, 86)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{751db496-4231-49ee-9be1-e48f7a2a2928}"
    }
  }
}