Examine source code of ChangeUser

{
  "manifest_version": 2,
  "name": "ChangeUser",
  "version": "1.1",
  "description": "change your google meet user in the page",
  "icons": {
    "48": "icons/icon-48.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://meet.google.com/*"
      ],
      "js": [
        "changeuser.js"
      ]
    }
  ],
  "browser_action": {
    "default_icon": "icons/icon-32.png",
    "default_title": "Change Meet User",
    "default_popup": "popup/popup.html"
  }
}