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is it possible to use Javascript to detect if an HTML element is currently overflowing?

Yes, it is possible to use JavaScript to detect if an HTML element is currently overflowing. To achieve this, you can compare the element’s clientWidth or clientHeight against its scrollWidth or scrollHeight. If the content exceeds these dimensions, it indicates that the element is overflowing. However, this method might not work correctly if the overflow property is set to visible, as the scrollWidth and scrollHeight would match the clientWidth and clientHeight.

Here’s a function that checks if an element is overflowing, taking into account the potential issue with the overflow property being set to visible:

function checkOverflow(el) {
    // Temporarily change the overflow style to 'hidden' to accurately measure overflow
    var curOverflow = el.style.overflow;
    if (!curOverflow || curOverflow === "visible") {
        el.style.overflow = "hidden";
    }

    // Check if the element is overflowing
    var isOverflowing = el.clientWidth < el.scrollWidth || el.clientHeight < el.scrollHeight;

    // Restore the original overflow style
    el.style.overflow = curOverflow;

    return isOverflowing;
}

// Example usage:
var myElement = document.getElementById('myElement');
if (checkOverflow(myElement)) {
    console.log('The element is overflowing.');
} else {
    console.log('The element does not overflow.');
}

This approach ensures that the overflow status is accurately determined by temporarily changing the overflow style to hidden during the measurement process. After checking, the original overflow style is restored to avoid any unintended side effects on the layout or appearance of the element [1][2].

Citations:
[1] https://www.geeksforgeeks.org/how-to-determine-the-content-of-html-elements-overflow-or-not/
[2] https://stackoverflow.com/questions/143815/determine-if-an-html-elements-content-overflows
[3] https://www.quora.com/With-JavaScript-how-can-you-detect-that-there-is-overflow-in-an-element-and-make-a-custom-element-appear-to-enable-scrolling-inside-that-element
[4] https://www.stevefenton.co.uk/blog/2022/12/detect-overflowing-elements/
[5] https://developer.mozilla.org/en-US/docs/Learn/CSS/Building_blocks/Overflowing_content
[6] https://github.com/w3c/csswg-drafts/issues/4123
[7] https://davidwalsh.name/detect-overflow-elements
[8] https://www.reddit.com/r/learnjavascript/comments/o08sos/how_to_detect_overflow_from_a_container/
[9] https://esdiscuss.org/topic/finding-elements-that-are-hidden-due-to-overflow-hidden
[10] https://forum.freecodecamp.org/t/adding-overflow-hidden-to-a-element-is-changing-the-position-of-elements-of-surrounding-it/398352