Checkboxes populate comment box as they should but erase data already in the comment box, anyone have a script that would fix that?

[leslier5639]

I have multiple checkboxes that when checked populate a comment box as they should. However, if there are comments already in the box it erases them. Any suggestions on how I keep that from happening? Thanks!

[try67]

Check if the field's value is empty before applying the new value to it.