I do not know why this is not mentioned in the API documentation, but if you call ace.edit in an already created editor, you will get this instance. This will NOT reset this editor. I tested it.
In your case, this can be done using the following code:
function handleDrop(e,obj) { var editor = ace.edit(obj.id);
I know that some time has passed since you asked this question, but I could not find anything on this topic, so I decided to share this.
Yoav kadosh
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