Validation message showing twice for invalid file format

Problem/Motivation

I have tried to upload an image file by managed_file. Also I have set allowed extensions for managed_file form field.

Error message showing twice for invalid file format.

Steps to reproduce the problem

Create a Form with below code for form elements.

  /**
   * {@inheritdoc}
   */
  public function buildForm(array $form, FormStateInterface $form_state) {
    $form['image'] = [
      '#type' => 'managed_file',
      '#title' => $this->t('Image ( allowed file formats: gif png jpg jpeg )'),
      '#upload_location' => 'public://upload/image',
      '#default_value' => '',
      '#upload_validators' => array(
        'file_validate_extensions' => array('gif png jpg jpeg'),
      ),
    ];

    $form['submit'] = [
        '#type' => 'submit',
        '#value' => t('Submit'),
    ];

    return $form;
  }

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