Post Randomizer v2

const stringArray = ["jan paweł 2", "tomasz terka","twój stary", "kosior", "testo"];

const button = document.createElement("button");
button.innerHTML = "Losuj";
button.classList.add("ladda-button");
button.setAttribute('type', 'button');

const fastForm = document.querySelector("#fastReplyButtons-tr");
fastForm.appendChild(button);

const textArea = document.querySelector(".blockquoteReply div textarea");

const randomize = (event) => {
  const randomText = stringArray[Math.floor(Math.random()*stringArray.length)];
  const target = event.target || event.srcElement;
  textArea.value += randomText || target.innerText;
};

button.addEventListener ("click", function() {
  randomize(event);
});