Examine source code of Online Twitch

{
  "description": "Addons for show if my stream is online",
  "manifest_version": 2,
  "name": "Online Twitch",
  "version": "1.0",
  "homepage_url": "https://github.com/thomaslasky/AddonFirefoxStream",
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "index.js"
      ]
    }
  ],
  "icons": {
    "96": "/img/icons/live_off.png"
  },
  "browser_action": {
    "browser_style": true,
    "default_title": "My Favorite Stream",
    "default_popup": "/templates/popup.html"
  },
  "background": {
    "scripts": [
      "/js/background.js"
    ]
  },
  "permission": [
    "storage"
  ]
}