Examine source code of Twitch open chat

{
  "name": "Twitch open chat",
  "version": "1.1",
  "description": "Automatically opens a channel's chat on Twitch.tv",
  "manifest_version": 2,
  "content_scripts": [
    {
      "matches": [
        "*://*.twitch.tv/*"
      ],
      "js": [
        "openChat.js"
      ]
    }
  ]
}