Inject script for DOM that often rerenders on start

reactInject.js

(() => {
  function injectButton(parent) {
    if (parent.querySelector(".pf_lb2")) return; // Prevent duplicates

    const wrapper = document.createElement("div");
    wrapper.innerHTML = `<!-- CONTENT -->`;
    parent.prepend(wrapper);
  }

  function waitForReactElement(attempts = 0, maxAttempts = 100) {
    const selector = ".parent";

    const check = () => {
      const parent = document.querySelector(selector);
      if (parent) {
        injectButton(parent);
        observeChanges(parent);
      } else if (attempts < maxAttempts) {
        setTimeout(() => waitForReactElement(attempts + 1, maxAttempts), 200);
      } else {
        console.warn(`Element '${selector}' not found after ${maxAttempts} attempts.`);
      }
    };

    check();
  }

  function observeChanges(target) {
    const observer = new MutationObserver(() => injectButton(target));
    observer.observe(target, { childList: true, subtree: true });
  }

  waitForReactElement();
})();