Examine source code of PagePocket

{
  "manifest_version": 2,
  "name": "PagePocket",
  "version": "1.0",
  "description": "Save articles for offline reading with enhanced features",
  "icons": {
    "48": "icons/pagepocket-48.png",
    "96": "icons/pagepocket-96.png"
  },
  "permissions": [
    "storage",
    "tabs",
    "<all_urls>",
    "webRequest",
    "webRequestBlocking",
    "downloads"
  ],
  "browser_action": {
    "default_icon": "icons/pagepocket-48.png",
    "default_title": "PagePocket",
    "default_popup": "popup/popup.html"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "options_ui": {
    "page": "options/options.html",
    "open_in_tab": true
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{bfc97fde-7206-4dd2-914b-c2349f615f90}"
    }
  }
}