Answers for "bootstrap loading spinner on form submit"

circlular waiting icon bootstrap

<div class="spinner-border" role="status">
  <span class="sr-only">Loading...</span>
</div>

bootstrap loader

<div class="clearfix">
  <div class="spinner-border float-right" role="status">
    <span class="sr-only">Loading...</span>
  </div>
</div>