Answers for "can we add jquery in chrome extension js code"

can we add jquery in chrome extension js code

You can just put jquery.js into extension folder and include it in the manifest:

{
  "name": "My extension",
  ...
  "content_scripts": [
    {
      "matches": ["http://www.google.com/*"],
      "css": ["mystyles.css"],
      "js": ["jquery.js", "myscript.js"]
    }
  ],
  ...
}
You don't need to worry about conflicts with jQuery on a parent page as content scripts are sandboxed.

jquery chrome extension

"content_security_policy": "script-src 'self' https://ajax.googleapis.com; object-src 'self'",