[Violation] Added non-passive event listener to a scroll-blocking 'touchstart' event. Consider marking event handler as 'passive' to make the page more responsive. See https://www.chromestatus.com/feature/5745543795965952

That message is a warning from Chrome letting you know that something on the page has attached a touchstart event listener without specifying { passive: true }. When the browser sees a non-passive touchstart, it has to assume the handler might call event.preventDefault(), so it can’t optimize scrolling, which can make the page feel less smooth.

To resolve it, locate the code that adds the touchstart (or touchmove) listener and mark it as passive if it doesn’t need to call preventDefault(). For example:

element.addEventListener('touchstart', handler, { passive: true });

If you do need to prevent default behavior, you’ll have to keep it non-passive and accept the warning (though generally there are ways to avoid forcing a non-passive listener). This change improves responsiveness and removes the warning.