Twitter - Delegated Listener

listener-jQuery.js

$("body").on("click", ".rectangle", function(e) {
  console.log("jquery", this)
  // do stuff
});

listener-vanilla.js

document.body.addEventListener("click", e => {
  if (e.target.matches(".rectangle")) {
      console.log("vanilla", e.target);
      // do stuff
  }
});