Since a few weeks, I got this event related warning (actually some code execution error). To find the faulty one, I should uninstall every single extensions (have a lot), startup scripts and etc. until I get rid of the message.
That lead me to the question, rather than doing that looooooong iterative process, I was wondering if I could climb up from eventListener instance to the script which added it. I said Script but of course that could be a CEP panel working on.
My feeling is that it's not possible (as I couldn't get get any useful prop in DOM). But hey, as soon as I state it, someone is showing me I am wrong