Debugging with Console & DevTools

Which type of breakpoint would be most helpful for debugging this event handler?

document.getElementById('login-form').addEventListener('submit', function(event) {
  event.preventDefault();
  const username = document.getElementById('username').value;
  const password = document.getElementById('password').value;
  // Login logic here
});

Line breakpoint
XHR breakpoint
Event listener breakpoint
Event listener breakpoints provide specialized event debugging: 1) They pause execution when specific types of events are triggered, 2) In DevTools, you can select specific event categories like 'Mouse', 'Keyboard', or even specific events like 'submit', 3) This would pause execution right at the beginning of the submit event handler, 4) No need to find the specific line in the code where the handler is defined, 5) This works even for events added dynamically or in external libraries, 6) It captures all handlers for the selected event type, helping discover hidden listeners, 7) This is much more reliable than searching for addEventListener calls in the code, 8) Event listener breakpoints are particularly valuable when debugging complex event-driven applications with many event handlers.
DOM breakpoint

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