How to debug an asynchronous loaded JS file

Recently developed features in a new Web project. The management interface of this project has a feature that the framework is fixed and does not refresh every time the new page is refreshed only by a Div. Div is not a set of IFRAME, resulting in a problem, with the browser can not debug the asynchronous loading page contains the JS file. Simply put, in the debugging tool can not see the asynchronous loading page contains the JS file.

Online found a solution, is to debug the top of the JS file add a line of code:

@ sourceurl=msgprompt.js

Note that there must be spaces between the @ symbol and the sourceURL. Chrome Bottom Effect:

Firefox is OK, too. That's a good idea.

How to debug an asynchronous loaded JS file