вывод данных из localStorage с помощью JSON.parse

function addMsg() { 
	let doc = document, 
		msgName,  
		msgDesc,  
		msgDate,  
		html; 
	if (doc.getElementById('name').value) { 
		msgName = doc.getElementById('name').value; 
	} else { 
		doc.getElementById('name').focus(); 
		return; 
	} 
	if (doc.getElementById('desc').value) { 
		msgDesc = doc.getElementById('desc').value 
	} else { 
		doc.getElementById('desc').focus(); 
		return; 
	} 
	msgDate = doc.getElementById('date').value = new Date(); 
	html = '<section class="msg"><div><span>By ' + msgName + '</span><span>' + msgDate + '</span></div> <p>' + msgDesc + '</p></section>'; 
	 
	let test = { 
		name: msgName,  
		desc: msgDesc, 
		date: msgDate  
	} 
	 
	localStorage.setItem('test', JSON.stringify(test));	 
	 
	//if (doc.getElementById('result').innerHTML += html) doc.forms.myform.reset(); 
	 
	let testMSG = JSON.parse(localStorage.getItem("test")); 
	 
	if (doc.getElementById('testMSG').innerHTML += html) doc.forms.myform.reset(); 
}

input, 
textarea { 
  width: 100%; 
  box-sizing: border-box; 
} 
 
section { 
  background: #e9e9e9; 
  border: 1px solid #ccc; 
  width: 320px; 
  margin: 3px; 
} 
 
p { 
  border: 1px solid #666; 
  margin: 3px; 
  padding: 5px; 
  font-size: 14px; 
} 
 
span { 
  font-size: 12px; 
  margin: 5px; 
}

<aside class="right" id="testMSG"> 
</aside> 
 
<!-- form msg comm --> 
<section class="form-box"> 
  <form id="myform" action=""> 
    <input id="name" value="" placeholder="Type your nickname here..." name="login" > 
    <textarea id="desc" placeholder="Write your comment here..." name="msg"></textarea> 
    <input id="date" type="hidden" /> 
    <input value="OK" type="button" onclick="addMsg()" />     
  </form> 
</section>