Upload Progress Bar in Contact Form 7

I reproduced successfully the solution described here to add one progress bar to CF7. But my Contact Form 7 doesn't validate required fields and does't show any response message after one click on the submit button.

I tried to adapt the code in scripts.js (contact-form-7/includes/js/scripts.js) from Version 3.5.3 to the newer version 5.1

Here is the changed scripts.js:

( function( $ ) {

    'use strict';
    	// start
    	var progressbox  = jQuery('#progressbox');
        var progressbar     = jQuery('#progressbar');
        var statustxt   = jQuery('#statustxt');
        var submitbutton    = jQuery("#SubmitButton");
        var myform  = jQuery("#wpcf7-form");
        var output2  = jQuery("#output2");
        var completed   = '0%';
    	//end

    if ( typeof wpcf7 === 'undefined' || wpcf7 === null ) {
    	return;
    }

    wpcf7 = $.extend( {
    	cached: 0,
    	inputs: []
    }, wpcf7 );

    $( function() {
    	wpcf7.supportHtml5 = ( function() {
    		var features = {};
    		var input = document.createElement( 'input' );

    		features.placeholder = 'placeholder' in input;

    		var inputTypes = [ 'email', 'url', 'tel', 'number', 'range', 'date' ];

    		$.each( inputTypes, function( index, value ) {
    			input.setAttribute( 'type', value );
    			features[ value ] = input.type !== 'text';
    		} );

    		return features;
    	} )();

    	$( 'div.wpcf7 > form' ).each( function() {
    		var $form = $( this );
    		wpcf7.initForm( $form );

    		if ( wpcf7.cached ) {
    			wpcf7.refill( $form );
    		}
    	} );
    } );

    wpcf7.getId = function( form ) {
    	return parseInt( $( 'input[name="_wpcf7"]', form ).val(), 10 );
    };

    wpcf7.initForm = function( form ) {
    	var $form = $( form );

    	$form.submit( function( event ) {
    		if ( ! wpcf7.supportHtml5.placeholder ) {
    			$( '[placeholder].placeheld', $form ).each( function( i, n ) {
    				$( n ).val( '' ).removeClass( 'placeheld' );
    			} );
    		}

    		if ( typeof window.FormData === 'function' ) {
    			wpcf7.submit( $form );
    			event.preventDefault();
    		}
    	} );

    	$( '.wpcf7-submit', $form ).after( '<span class="ajax-loader"></span>' );

    	wpcf7.toggleSubmit( $form );

    	$form.on( 'click', '.wpcf7-acceptance', function() {
    		wpcf7.toggleSubmit( $form );
    	} );

    	// Exclusive Checkbox
    	$( '.wpcf7-exclusive-checkbox', $form ).on( 'click', 'input:checkbox', function() {
    		var name = $( this ).attr( 'name' );
    		$form.find( 'input:checkbox[name="' + name + '"]' ).not( this ).prop( 'checked', false );
    	} );

    	// Free Text Option for Checkboxes and Radio Buttons
    	$( '.wpcf7-list-item.has-free-text', $form ).each( function() {
    		var $freetext = $( ':input.wpcf7-free-text', this );
    		var $wrap = $( this ).closest( '.wpcf7-form-control' );

    		if ( $( ':checkbox, :radio', this ).is( ':checked' ) ) {
    			$freetext.prop( 'disabled', false );
    		} else {
    			$freetext.prop( 'disabled', true );
    		}

    		$wrap.on( 'change', ':checkbox, :radio', function() {
    			var $cb = $( '.has-free-text', $wrap ).find( ':checkbox, :radio' );

    			if ( $cb.is( ':checked' ) ) {
    				$freetext.prop( 'disabled', false ).focus();
    			} else {
    				$freetext.prop( 'disabled', true );
    			}
    		} );
    	} );

    	// Placeholder Fallback
    	if ( ! wpcf7.supportHtml5.placeholder ) {
    		$( '[placeholder]', $form ).each( function() {
    			$( this ).val( $( this ).attr( 'placeholder' ) );
    			$( this ).addClass( 'placeheld' );

    			$( this ).focus( function() {
    				if ( $( this ).hasClass( 'placeheld' ) ) {
    					$( this ).val( '' ).removeClass( 'placeheld' );
    				}
    			} );

    			$( this ).blur( function() {
    				if ( '' === $( this ).val() ) {
    					$( this ).val( $( this ).attr( 'placeholder' ) );
    					$( this ).addClass( 'placeheld' );
    				}
    			} );
    		} );
    	}

    	if ( wpcf7.jqueryUi && ! wpcf7.supportHtml5.date ) {
    		$form.find( 'input.wpcf7-date[type="date"]' ).each( function() {
    			$( this ).datepicker( {
    				dateFormat: 'yy-mm-dd',
    				minDate: new Date( $( this ).attr( 'min' ) ),
    				maxDate: new Date( $( this ).attr( 'max' ) )
    			} );
    		} );
    	}

    	if ( wpcf7.jqueryUi && ! wpcf7.supportHtml5.number ) {
    		$form.find( 'input.wpcf7-number[type="number"]' ).each( function() {
    			$( this ).spinner( {
    				min: $( this ).attr( 'min' ),
    				max: $( this ).attr( 'max' ),
    				step: $( this ).attr( 'step' )
    			} );
    		} );
    	}

    	// Character Count
    	$( '.wpcf7-character-count', $form ).each( function() {
    		var $count = $( this );
    		var name = $count.attr( 'data-target-name' );
    		var down = $count.hasClass( 'down' );
    		var starting = parseInt( $count.attr( 'data-starting-value' ), 10 );
    		var maximum = parseInt( $count.attr( 'data-maximum-value' ), 10 );
    		var minimum = parseInt( $count.attr( 'data-minimum-value' ), 10 );

    		var updateCount = function( target ) {
    			var $target = $( target );
    			var length = $target.val().length;
    			var count = down ? starting - length : length;
    			$count.attr( 'data-current-value', count );
    			$count.text( count );

    			if ( maximum && maximum < length ) {
    				$count.addClass( 'too-long' );
    			} else {
    				$count.removeClass( 'too-long' );
    			}

    			if ( minimum && length < minimum ) {
    				$count.addClass( 'too-short' );
    			} else {
    				$count.removeClass( 'too-short' );
    			}
    		};

    		$( ':input[name="' + name + '"]', $form ).each( function() {
    			updateCount( this );

    			$( this ).keyup( function() {
    				updateCount( this );
    			} );
    		} );
    	} );

    	// URL Input Correction
    	$form.on( 'change', '.wpcf7-validates-as-url', function() {
    		var val = $.trim( $( this ).val() );

    		if ( val
    		&& ! val.match( /^[a-z][a-z0-9.+-]*:/i )
    		&& -1 !== val.indexOf( '.' ) ) {
    			val = val.replace( /^\/+/, '' );
    			val = 'http://' + val;
    		}

    		$( this ).val( val );
    	} );
    };

    wpcf7.submit = function( form ) {
    	if ( typeof window.FormData !== 'function' ) {
    		return;
    	}

    	var $form = $( form );

    	$( '.ajax-loader', $form ).addClass( 'is-active' );

    	wpcf7.clearResponse( $form );

    	var formData = new FormData( $form.get( 0 ) );

    	var detail = {
    		id: $form.closest( 'div.wpcf7' ).attr( 'id' ),
    		status: 'init',
    		inputs: [],
    		formData: formData
    	};

    	$.each( $form.serializeArray(), function( i, field ) {
    		if ( '_wpcf7' == field.name ) {
    			detail.contactFormId = field.value;
    		} else if ( '_wpcf7_version' == field.name ) {
    			detail.pluginVersion = field.value;
    		} else if ( '_wpcf7_locale' == field.name ) {
    			detail.contactFormLocale = field.value;
    		} else if ( '_wpcf7_unit_tag' == field.name ) {
    			detail.unitTag = field.value;
    		} else if ( '_wpcf7_container_post' == field.name ) {
    			detail.containerPostId = field.value;
    		} else if ( field.name.match( /^_wpcf7_\w+_free_text_/ ) ) {
    			var owner = field.name.replace( /^_wpcf7_\w+_free_text_/, '' );
    			detail.inputs.push( {
    				name: owner + '-free-text',
    				value: field.value
    			} );
    		} else if ( field.name.match( /^_/ ) ) {
    			// do nothing
    		} else {
    			detail.inputs.push( field );
    		}
    	} );

    	wpcf7.triggerEvent( $form.closest( 'div.wpcf7' ), 'beforesubmit', detail );

    	var ajaxSuccess = function( data, status, xhr, $form ) {
    		detail.id = $( data.into ).attr( 'id' );
    		detail.status = data.status;
    		detail.apiResponse = data;

    		var $message = $( '.wpcf7-response-output', $form );
    		// start
    		submitbutton.attr('disabled', ''); // disable upload button
    		statustxt.empty();
    		progressbox.slideDown(); //show progressbar
    		progressbar.width(completed); //initial value 0% of progressbar
    		statustxt.html(completed); //set status text
    		statustxt.css('color','#000'); //initial color of status text
    		//end
    		
    		// start
    		uploadProgress: function(event, position, total, percentComplete) { //on progress
    			progressbar.width(percentComplete + '%') //update progressbar percent complete
    			statustxt.html(percentComplete + '%'); //update status text
    			if(percentComplete>50) {
    				statustxt.css('color','#fff'); //change status text to white after 50%
    			}
    		},
    		//end

    		switch ( data.status ) {
    			case 'validation_failed':
    				$.each( data.invalidFields, function( i, n ) {
    					$( n.into, $form ).each( function() {
    						wpcf7.notValidTip( this, n.message );
    						$( '.wpcf7-form-control', this ).addClass( 'wpcf7-not-valid' );
    						$( '[aria-invalid]', this ).attr( 'aria-invalid', 'true' );
    					} );
    				} );

    				$message.addClass( 'wpcf7-validation-errors' );
    				$form.addClass( 'invalid' );

    				wpcf7.triggerEvent( data.into, 'invalid', detail );
    				break;
    			case 'acceptance_missing':
    				$message.addClass( 'wpcf7-acceptance-missing' );
    				$form.addClass( 'unaccepted' );

    				wpcf7.triggerEvent( data.into, 'unaccepted', detail );
    				break;
    			case 'spam':
    				$message.addClass( 'wpcf7-spam-blocked' );
    				$form.addClass( 'spam' );

    				wpcf7.triggerEvent( data.into, 'spam', detail );
    				break;
    			case 'aborted':
    				$message.addClass( 'wpcf7-aborted' );
    				$form.addClass( 'aborted' );

    				wpcf7.triggerEvent( data.into, 'aborted', detail );
    				break;
    			case 'mail_sent':
    				$message.addClass( 'wpcf7-mail-sent-ok' );
    				$form.addClass( 'sent' );

    				wpcf7.triggerEvent( data.into, 'mailsent', detail );
    				break;
    			case 'mail_failed':
    				$message.addClass( 'wpcf7-mail-sent-ng' );
    				$form.addClass( 'failed' );

    				wpcf7.triggerEvent( data.into, 'mailfailed', detail );
    				break;
    			default:
    				var customStatusClass = 'custom-'
    					+ data.status.replace( /[^0-9a-z]+/i, '-' );
    				$message.addClass( 'wpcf7-' + customStatusClass );
    				$form.addClass( customStatusClass );
    		}

    		wpcf7.refill( $form, data );

    		wpcf7.triggerEvent( data.into, 'submit', detail );

    		if ( 'mail_sent' == data.status ) {
    			$form.each( function() {
    				this.reset();
    			} );

    			wpcf7.toggleSubmit( $form );
    		}

    		if ( ! wpcf7.supportHtml5.placeholder ) {
    			$form.find( '[placeholder].placeheld' ).each( function( i, n ) {
    				$( n ).val( $( n ).attr( 'placeholder' ) );
    			} );
    		}

    		$message.html( '' ).append( data.message ).slideDown( 'fast' );
    		$message.attr( 'role', 'alert' );

    		$( '.screen-reader-response', $form.closest( '.wpcf7' ) ).each( function() {
    			var $response = $( this );
    			$response.html( '' ).attr( 'role', '' ).append( data.message );

    			if ( data.invalidFields ) {
    				var $invalids = $( '<ul></ul>' );

    				$.each( data.invalidFields, function( i, n ) {
    					if ( n.idref ) {
    						var $li = $( '<li></li>' ).append( $( '<a></a>' ).attr( 'href', '#' + n.idref ).append( n.message ) );
    					} else {
    						var $li = $( '<li></li>' ).append( n.message );
    					}

    					$invalids.append( $li );
    				} );

    				$response.append( $invalids );
    			}

    			$response.attr( 'role', 'alert' ).focus();
    		} );
    	};

    	$.ajax( {
    		type: 'POST',
    		url: wpcf7.apiSettings.getRoute(
    			'/contact-forms/' + wpcf7.getId( $form ) + '/feedback' ),
    		data: formData,
    		dataType: 'json',
    		processData: false,
    		contentType: false
    	} ).done( function( data, status, xhr ) {
    		ajaxSuccess( data, status, xhr, $form );
    		$( '.ajax-loader', $form ).removeClass( 'is-active' );
    	} ).fail( function( xhr, status, error ) {
    		var $e = $( '<div class="ajax-error"></div>' ).text( error.message );
    		$form.after( $e );
    	} );
    };

    wpcf7.triggerEvent = function( target, name, detail ) {
    	var $target = $( target );

    	/* DOM event */
    	var event = new CustomEvent( 'wpcf7' + name, {
    		bubbles: true,
    		detail: detail
    	} );

    	$target.get( 0 ).dispatchEvent( event );

    	/* jQuery event */
    	$target.trigger( 'wpcf7:' + name, detail );
    	$target.trigger( name + '.wpcf7', detail ); // deprecated
    };

    wpcf7.toggleSubmit = function( form, state ) {
    	var $form = $( form );
    	var $submit = $( 'input:submit', $form );

    	if ( typeof state !== 'undefined' ) {
    		$submit.prop( 'disabled', ! state );
    		return;
    	}

    	if ( $form.hasClass( 'wpcf7-acceptance-as-validation' ) ) {
    		return;
    	}

    	$submit.prop( 'disabled', false );

    	$( '.wpcf7-acceptance', $form ).each( function() {
    		var $span = $( this );
    		var $input = $( 'input:checkbox', $span );

    		if ( ! $span.hasClass( 'optional' ) ) {
    			if ( $span.hasClass( 'invert' ) && $input.is( ':checked' )
    			|| ! $span.hasClass( 'invert' ) && ! $input.is( ':checked' ) ) {
    				$submit.prop( 'disabled', true );
    				return false;
    			}
    		}
    	} );
    };

    wpcf7.notValidTip = function( target, message ) {
    	var $target = $( target );
    	$( '.wpcf7-not-valid-tip', $target ).remove();
    	$( '<span role="alert" class="wpcf7-not-valid-tip"></span>' )
    		.text( message ).appendTo( $target );

    	if ( $target.is( '.use-floating-validation-tip *' ) ) {
    		var fadeOut = function( target ) {
    			$( target ).not( ':hidden' ).animate( {
    				opacity: 0
    			}, 'fast', function() {
    				$( this ).css( { 'z-index': -100 } );
    			} );
    		};

    		$target.on( 'mouseover', '.wpcf7-not-valid-tip', function() {
    			fadeOut( this );
    		} );

    		$target.on( 'focus', ':input', function() {
    			fadeOut( $( '.wpcf7-not-valid-tip', $target ) );
    		} );
    	}
    };

    wpcf7.refill = function( form, data ) {
    	var $form = $( form );

    	var refillCaptcha = function( $form, items ) {
    		$.each( items, function( i, n ) {
    			$form.find( ':input[name="' + i + '"]' ).val( '' );
    			$form.find( 'img.wpcf7-captcha-' + i ).attr( 'src', n );
    			var match = /([0-9]+)\.(png|gif|jpeg)$/.exec( n );
    			$form.find( 'input:hidden[name="_wpcf7_captcha_challenge_' + i + '"]' ).attr( 'value', match[ 1 ] );
    		} );
    	};

    	var refillQuiz = function( $form, items ) {
    		$.each( items, function( i, n ) {
    			$form.find( ':input[name="' + i + '"]' ).val( '' );
    			$form.find( ':input[name="' + i + '"]' ).siblings( 'span.wpcf7-quiz-label' ).text( n[ 0 ] );
    			$form.find( 'input:hidden[name="_wpcf7_quiz_answer_' + i + '"]' ).attr( 'value', n[ 1 ] );
    		} );
    	};

    	if ( typeof data === 'undefined' ) {
    		$.ajax( {
    			type: 'GET',
    			url: wpcf7.apiSettings.getRoute(
    				'/contact-forms/' + wpcf7.getId( $form ) + '/refill' ),
    			beforeSend: function( xhr ) {
    				var nonce = $form.find( ':input[name="_wpnonce"]' ).val();

    				if ( nonce ) {
    					xhr.setRequestHeader( 'X-WP-Nonce', nonce );
    				}
    			},
    			dataType: 'json'
    		} ).done( function( data, status, xhr ) {
    			if ( data.captcha ) {
    				refillCaptcha( $form, data.captcha );
    			}

    			if ( data.quiz ) {
    				refillQuiz( $form, data.quiz );
    			}
    		} );

    	} else {
    		if ( data.captcha ) {
    			refillCaptcha( $form, data.captcha );
    		}

    		if ( data.quiz ) {
    			refillQuiz( $form, data.quiz );
    		}
    	}
    };

    wpcf7.clearResponse = function( form ) {
    	var $form = $( form );
    	$form.removeClass( 'invalid spam sent failed' );
    	$form.siblings( '.screen-reader-response' ).html( '' ).attr( 'role', '' );

    	$( '.wpcf7-not-valid-tip', $form ).remove();
    	$( '[aria-invalid]', $form ).attr( 'aria-invalid', 'false' );
    	$( '.wpcf7-form-control', $form ).removeClass( 'wpcf7-not-valid' );

    	$( '.wpcf7-response-output', $form )
    		.hide().empty().removeAttr( 'role' )
    		.removeClass( 'wpcf7-mail-sent-ok wpcf7-mail-sent-ng wpcf7-validation-errors wpcf7-spam-blocked' );
    };

    wpcf7.apiSettings.getRoute = function( path ) {
    	var url = wpcf7.apiSettings.root;

    	url = url.replace(
    		wpcf7.apiSettings.namespace,
    		wpcf7.apiSettings.namespace + path );

    	return url;
    };

} )( jQuery );

/*
 * Polyfill for Internet Explorer
 * See https://developer.mozilla.org/en-US/docs/Web/API/CustomEvent/CustomEvent
 */
( function () {
    if ( typeof window.CustomEvent === "function" ) return false;

    function CustomEvent ( event, params ) {
    	params = params || { bubbles: false, cancelable: false, detail: undefined };
    	var evt = document.createEvent( 'CustomEvent' );
    	evt.initCustomEvent( event,
    		params.bubbles, params.cancelable, params.detail );
    	return evt;
    }

    CustomEvent.prototype = window.Event.prototype;

    window.CustomEvent = CustomEvent;
} )();

The progessbar works very good, mails are sended, but if the upload reach 100% the ajax-loader is still spinnig and the success message does not appear.

Can someone help to get it working?