Examine source code of Knowfox

{
  "manifest_version": 2,
  "name": "Knowfox",
  "version": "0.2resigned1",
  "description": "Save bookmarks to Knowfox",
  "homepage_url": "https://github.com/knowfox/firefox-extension",
  "icons": {
    "48": "icons/knowfox-48.png",
    "96": "icons/knowfox-96.png"
  },
  "permissions": [
    "activeTab",
    "tabs",
    "<all_urls>",
    "cookies"
  ],
  "browser_action": {
    "default_icon": "icons/knowfox-32.png",
    "default_title": "Knowfox!",
    "default_popup": "popup.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{dc17a8c6-30f4-4d7b-9424-2df5639f381b}"
    }
  }
}