User:Zackmann08/scripts/wait.js

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Documentation for this user script can be added at User:Zackmann08/scripts/wait.

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/**
	importScript('User:Zackmann08/scripts/wait.js');
	(async () => {
		await waitForElement("elementIdentifier");
		// Do something here
	})();
 */


function waitForElement(selector) {
  return new Promise(resolve => {
    // Check if it already exists
    const element = document.querySelector(selector);
    if (element) {
      return resolve(element);
    }

    // Observe changes if it doesn't exist yet
    const observer = new MutationObserver(mutations => {
      const element = document.querySelector(selector);
      if (element) {
        resolve(element);
        observer.disconnect(); // Stop observing once found
      }
    });

    observer.observe(document.body, {
      childList: true,
      subtree: true
    });
  });
}