Examine source code of Bring Maps Back

{
  "$schema": "https://json.schemastore.org/webextension.json",
  "manifest_version": 2,
  "name": "Bring Maps Back",
  "version": "2.0.1",
  "description": "Brings back the \"Maps\" button in google.com",
  "content_scripts": [
    {
      "matches": [
        "https://www.google.com/search*"
      ],
      "js": [
        "main.js"
      ],
      "run_at": "document_end"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{d0112075-20e5-4923-9b58-0ba8f7501e8c}"
    }
  }
}