Are there any practical ways to tell what part of the DOM was modified if you know that it will be modified?
I am writing a plugin that will be running along with ja
You could also do a hash of the page text (e.g. complete source string) and compare it (on change) to current hash.
Depending on the browser support you need, you may be able to use DOM mutation events.
With jquery you could trigger :animated filter to search the elements being animated, i don't know if you will have so much delay between these kind of events, but if main trigger on initial transform is triggered just when transformation is initiated you could try to catch :animated element and capture initial state before ending animation, then on end capture state and compare, its only a hint i don't have any demonstration or way to reproduce your working environment but i hope this guideline could give you a idea.
This is not possible in any practical manner
A possibility, if you know what aspect of the DOM elements are to be modified, is to store the value of that attribute in a .data() node for each element on page load, then compare after the script is run.