JSFiddle - React, Tailwind, and code Playground
HTML
<button>backSpace</button>
<div id = "mainDiv" contenteditable="true">asd</div>
JavaScript
function backSpace()
{
var txt = $("#mainDiv").text();
txt = txt.substr(0,txt.length-1)
$("#mainDiv").text(txt);
}
$(document).ready(function(){
$('button').click(backSpace);
});