Search for an element until found using JavaScript

A nice piece of code to use for A/B testing to look for a certain element every 50 milliseconds, execute the code when found, then clear the interval loop. If the element is not found the loop is interrupted after 15 seconds.

var ytTimeoutId;

window.onload = function() {
    ytTimeoutId = setInterval(function() {
        // Check for a specific element ID
        if (document.getElementById('element')) {
            // Do stuff

            window.clearInterval(ytTimeoutId);
        }
    }, 50);

    setTimeout(function() {
        window.clearInterval(ytTimeoutId);
    }, 15000);
}

Change the interval ping value or the general timeout value (15 seconds) as you see fit.

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