Stop YouTube Play on Load

stop-youtube-play-on-load.js

(() => {
  let isInitialized = false; // Flag to indicate if the initial pause has been done

  const pauseVideo = () => {
    if (isInitialized) return; // If the initial pause has been done, do nothing further

    const video = document.querySelector('#movie_player > div.html5-video-container > video');
    
    // Pause the video if it's found and playing, and then perform cleanup
    if (video && !video.paused) {
      video.pause();
      isInitialized = true;
      cleanup(); // Clean up immediately after pausing
    }
  };

  const videoCheckInterval = setInterval(pauseVideo, 1000);

  const observer = new MutationObserver(mutations => {
    mutations.forEach(mutation => {
      mutation.addedNodes.forEach(node => {
        if (node.matches('#movie_player > div.html5-video-container > video')) {
          pauseVideo();
        }
      });
    });
  });

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

  const cleanup = () => {
    clearInterval(videoCheckInterval);
    observer.disconnect();
    window.removeEventListener('beforeunload', cleanup);
  };

  window.addEventListener('beforeunload', cleanup);
})();