add-jquery-to-website-via-console.js

// add script (e.g jQuery) to current website via console (lives only within the client)
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);