I'm not sure there's enough info here to answer your question, but maybe I can
When you say you need to paste text, you mean your _users_ need to paste text?
Or do you mean you are doing it programmatically?
If you are copying/binding/pasting the text programmatically, then you can
manually dispatch the paste event if you need to when you do the actual
operation. There's info about dispatching events manually in the docs.
As for using this.addEventListener, I am not sure you want to use "this" -- in
most contexts, that refers to the application itself and not a specific
component such as the HTMLLoader. Just mentioning this in case its what's
causing your problem.