To answer my own question. The documentation for Chooser happens to mention that the action is called <On Change>.
I think it would make life much easier, if there exists one default action that works on all elements that support event handlers, and those that support additional ones can then add yet a different type of event handler that they support.
I.e. all elements that support a single event handler only could for instance support the <On Click> event handler, and those that support multiple distinct event handlers would support <On Click> for click events, plus event handlers named differently for whatever other functions they support.
Granted, in some instances, a different name for the single support event handler may be more descriptive, but I wonder it also leaves on guessing, which event handler to use in the particular instance.
I'm curious what you think.
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