Examine source code of Brewconvert

{
  "manifest_version": 2,
  "name": "Brew Convert",
  "version": "1.2resigned1",
  "permissions": [
    "contextMenus",
    "storage"
  ],
  "description": "Convert highlighted text to different units common for homebrewing.",
  "default_locale": "en",
  "icons": {
    "16": "icons/brewvert_16.png",
    "32": "icons/brewvert_32.png",
    "48": "icons/brewvert_48.png",
    "64": "icons/brewvert_64.png",
    "128": "icons/brewvert_128.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "options_ui": {
    "page": "options.html"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content-script.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{c0711be6-3e5a-4e55-8171-cf74c1a8d80b}"
    }
  }
}