I am studying this page: http://www.fxstreet.com/rates-charts/currency-rates/ which is continually updated by JavaScript with new data from the server. So clearly there is some JavaScript function continually executing in the page. So I opened Firebug and I don't see any "profiler" type output that would continually add new info about executing scripts. The "script" tab only shows 46 not very clear records, without timestamps and without any indication that there is continual new JavaScript activity to profile.
What am I doing wrong? How do I go about groking the JavaScript activity on a page?
In the Console tab of Firebug there is a Profile button next to Clear and Persist, which does what you're trying to do. It's not real-time but you can let it run for a certain time period and analyse the results afterwards which should show you what you're looking for.