Question

Is there a way to have this prototype js trigger only when dom is changed and not loaded?

Answer 1

you can observe elements changing like this

$('element').observe('change',function(e){ } );

This is reserved for form elements though – textarea, select and input.

The final code would look something like:

document.observe('dom:loaded', function() {
    $('element').observe('change',function(e){
    // do something here
    });
});