Examine source code of SecondChat

{
  "manifest_version": 2,
  "name": "SecondChat",
  "version": "1.0",
  "description": "Add a common chat to the web page for all the websites.",
  "icons": {
    "48": "icons/border-48.png"
  },
  "browser_action": {
    "browser_style": true,
    "default_popup": "popup/popup.html",
    "default_icon": {
      "48": "icons/border-48.png"
    }
  },
  "permissions": [
    "storage",
    "tabs"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{95550efa-b9ab-4ded-ad11-cfc0caecede5}"
    }
  }
}