on click outside div javascript

JavaScript
document.addEventListener("click", (evt) => {
    const flyoutElement = document.getElementById("flyout-example");
    let targetElement = evt.target; // clicked element

    do {
        if (targetElement == flyoutElement) {
            // This is a click inside. Do nothing, just return.
            document.getElementById("flyout-debug").textContent = "Clicked inside!";
            return;
        }
        // Go up the DOM
        targetElement = targetElement.parentNode;
    } while (targetElement);

    // This is a click outside.
    document.getElementById("flyout-debug").textContent = "Clicked outside!";
});

Source

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