Examine source code of jellyfishes

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "jellyfish",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.jpg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "left bottom"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(148, 184, 210)",
      "toolbar_text": "rgb(2, 45, 88)",
      "frame": "rgb(142, 179, 201)",
      "tab_background_text": "rgb(255, 255, 255)",
      "toolbar_field": "rgb(255, 255, 255)",
      "toolbar_field_text": "rgb(123, 127, 204)",
      "tab_line": "rgb(4, 49, 55)",
      "popup": "rgb(255, 255, 255)",
      "popup_text": "rgb(98, 102, 183)",
      "tab_loading": "rgb(4, 49, 55)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{5a5a7dc0-2e26-490e-a771-88e16962d0ef}"
    }
  }
}