how to use jquery in chrome extension code example

Example 1: how to use jquery in chrome dev tools

var jq = document.createElement('script');
jq.src = "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js";
document.getElementsByTagName('head')[0].appendChild(jq);
// ... give time for script to load, then type (or see below for non wait option)
jQuery.noConflict();

Example 2: jquery chrome extension

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

Example 3: 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.