Frontend & browser·JavaScript in the browser
you stopped the form from navigating away but the parent's handler still ran.
preventDefault
Also calledprevent default action
Cancelling the browser's built-in response to an event — following a link, submitting a form, scrolling on a wheel event — without affecting propagation at all. It is routinely confused with stopping propagation because both are called in the same handler, but they do unrelated things. It has no effect on a non-cancelable event, and none at all on a passive listener.