Javascript - How to save an array to clipboard for excel

Question

I want to save an array from a table to clipboard. It could be compatible with excel. Is it possible to use execCommand()?

A small example:

<div style="display:inline-flex;">
   <div id="11">
        1
   </div>
   <div id="12">
        2
   </div>
</div>
<div style="display:inline-flex;">
   <div id="21">
        3
   </div>
   <div id="22">
        4
   </div>
</div>
<button id="save">Save</button>

<script>
   var save = document.getElementById('save');
   var a =  document.getElementById('12');
   var b =  document.getElementById('22');
   save.addEventListener('click', function () {
       document.execCommand('copy',[a,b]);
   });

</script>

Now i want to copy the arry to excel. That should be the result:

2| | |
------ 
4| | |