I am newly working on a fairly old system, which uses ColdFusion if it matters. In various places, it uses Ajax.Updater for server requests which return new HTML (.cfm) fragments to update the specified element with. This HTML also includes JavaScript via <script>'s and inline event handlers, ie. <button onclick=...

The question is how can I go about debugging this code?

HTML (and .cfm) documents typically show up in the sources tab and can be debugged like normal JS, but in both Chrome and Firefox, the fetched HTML is not showing up. I can clearly see the new html being fetched in the network tab, the new elements are rendered and appear in the elements tab, and the actual JavaScript is clearly running as expected; it just doesn't show up in the debugger.

Does fetched code simply never go to the debugger? Is it because the fetched html is a fragment? Is there some other known way to debug code from Ajax requested HTML?