form.addEventListener('submit', function (event) { if (!email.validity.valid) { event.preventDefault() showError() } }) function showError() { if (email.validity.valueMissing) { emailError.innerHTML = 'Email is required' } else if (email.validity.typeMismatch) { emailError.innerHTML = 'Please enter a valid email address' } email.classList.add('is-invalid') }

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