Require a title in the WordPress Edit Post screen

require-title.js

$('body').on( 'submit.edit-post', '#post', function () {

	// If the title isn't set
	if( $("#title").val().length === 0 ) {

		// Show the alert
		alert('A title is required.');

		// Hide the spinner
		$('#major-publishing-actions .spinner').hide();

		// The buttons get "disabled" added to them on submit. Remove that class.
		$('#major-publishing-actions').find( ':button, :submit, a.submitdelete, #post-preview' ).removeClass( 'disabled' );

		// Focus on the title field.
		$("#title").focus();

		return false;
	}

});