Examine source code of Share Website Sessions

{
  "manifest_version": 2,
  "name": "Share Website Sessions",
  "version": "1.1resigned1",
  "description": "Allows you to share already signed into website sessions with your friends or your other devices via email, chat, or Firefox's Synced Tabs functionality.",
  "homepage_url": "https://github.com/GuidedCommerce/FirefoxSyncLoggedInTabs",
  "icons": {
    "48": "icons/browser-48.png"
  },
  "permissions": [
    "alarms",
    "cookies",
    "<all_urls>",
    "webNavigation",
    "browsingData",
    "tabs"
  ],
  "page_action": {
    "default_icon": "icons/browser-32.png",
    "default_title": "Share Website Sessions"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "applications": {
    "gecko": {
      "id": "guidedcommerce@gmail.com"
    }
  }
}