Examine source code of Better Drive Chat

{
  "manifest_version": 2,
  "name": "Better Drive Chat",
  "description": "Emotes and images in Google Docs chat.",
  "version": "1.2.1",
  "homepage_url": "https://github.com/xoko14/gdocs-chat-emotes",
  "icons": {
    "48": "icon.png",
    "96": "icon@2x.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://docs.google.com/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "web_accessible_resources": [
    "db/emotelist.json"
  ]
}