Removing DOM element from parent that loads onClick

removeFirst.js

window.addEventListener("DOMContentLoaded", function() {
    const targetNode = document.getElementById('rpressModal')

    const config = { attributes: true, childList: true, subtree: true };

    const removeFirst = (e) => {
      e.selectedIndex = "2";
    }

    const callback = function(mutationsList, observer) {
  	for(const mutation of mutationsList) {
        if (mutation.type === 'childList') {
            console.log('A child node has been added or removed.');
          	let firstLoop = true
            if(firstLoop){
              const select = document.getElementById('rpress-pickup-hours')
            	removeFirst(select)
            } else { return }
        }
    }
	};

	const observer = new MutationObserver(callback);

	observer.observe(targetNode, config);
    
  }, false);