preventDefault vs stopPropagation?
Quick answer
preventDefault cancels the browser's default action; stopPropagation stops the event from travelling further through the DOM.
In detail
`e.preventDefault()` stops the default behaviour (form submit, link navigation) but the event still bubbles. `e.stopPropagation()` halts propagation to ancestors but the default action still happens. They're independent; sometimes you need both.
form.addEventListener("submit", (e) => {
e.preventDefault(); // don't reload the page
submitViaAjax();
});Why interviewers ask this: Commonly confused — interviewers check you know the difference.
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