title: How to set a value in a select2 combobox
body: <p>I need to auto-fill a form that is using select2 comboboxes. The classic JS code <code>document.getElementById('id').value = 'value';</code> isn't working, nor do I wish to include jQuery for what should be a simple operation, unless absolutely unavoidable. Are there any JS alternatives to this problem ?</p>
  
  <p>I have no control over the HTML, so changing the boxes isn't an option, unfortunately.</p>