  <!DOCTYPE html>
    <html lang="en">
    
    <!-- include libraries(jQuery, bootstrap) -->
    <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.1.3/dist/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-1BmE4kWBq78iYhFldvKuhfTAU6auU8tT94WrHftjDbrCEXSU1oBoqyl2QvZ6jIW3" crossorigin="anonymous">
    <script src="https://code.jquery.com/jquery-3.5.1.min.js"></script>
    <script src="https://cdn.jsdelivr.net/npm/bootstrap@5.1.3/dist/js/bootstrap.bundle.min.js" integrity="sha384-ka7Sk0Gln4gmtz2MlQnikT1wXgYsOg+OMhuP+IlRH9sENBO0LRn5q+8nbTov4+1p" crossorigin="anonymous"></script>
    
    <!-- include summernote css/js -->
    <link href="https://cdn.jsdelivr.net/npm/summernote@0.8.18/dist/summernote.min.css" rel="stylesheet">
    <script src="https://cdn.jsdelivr.net/npm/summernote@0.8.18/dist/summernote.min.js"></script>
    
    <div class="mt-2">
        <label class="control-label" for="textarea">Descrizione breve:</label>
        <textarea class="summernote" name="content_abstract">blabla</textarea>
    </div>
    
<script>

$(document).ready(function() {
      $('.summernote').summernote();
    });

</script>    

    </html>