Corvuss

const centerX = targetNode.offsetLeft + targetNode.offsetWidth / 2;
const centerY = targetNode.offsetTop + targetNode.offsetHeight / 2;

HTMLElement.prototype.waitFor = function(event_name) {
    if (event_name) {
        return new Promise((res, rej) => {
        	const listener = function() {
        		res()
        		this.removeEventListener(event_name, listener)
        	};

        	this.addEventListener(event_name, listener);
        })
    } else {
        throw 'No event passed to waitFor method!';
    }
}

async function foo() {
	const start = new Date();
	await document.querySelector('body').waitFor('click');
	console.log('uspeshno dojdalis clicka, jdali celih ' + ((new Date().getTime() - start.getTime())/1000) + ' sekund');
}

foo();