jQuery Simple Example

HTML

<script src="//www.addressfinder.co.nz/assets/v2/widget.js"></script>

<p autocomplete="off" autocorrect="off" autocapitalize="off" spellcheck="false" contenteditable="true" placeholder="Enter text..." maxlength="10" class="entry__text"></p>

CSS

p{
  border: 1px solid black;
}

JavaScript

$(document).ready(function() {
  
  var limitNum = 10;
  $("p[contenteditable='true'][maxlength]").on('keydown paste', function (event) {
     var cntMaxLength = parseInt($(this).attr('maxlength'));

     if ($(this).text().length === cntMaxLength && event.keyCode != 8) {
         event.preventDefault();
     }
});
  
});