Can not properly record activity due to error "event start exceeds event end"

What steps will reproduce the problem?  If possible, include the full Url
of any web page you see a problem on.
1. Open FireFox 3.5 using FireBug 1.4.0b7 with Page Speed 1.0.1.1
2. Go to http://www.swaptree.com
3. Attempt to view activity
4. Page Speed Error

What is the expected output? What do you see instead?
No exception. 

Page Speed Activity encountered an error:
Error("event start exceeds event end")@:0
([object Object],8160000)@chrome://activity/content/observer-base.js:314
()@chrome://activity/content/observer-base.js:177
(-9)@chrome://activity/content/timeline-manager.js:304
(-9)@chrome://activity/content/base.js:906
((function (exception) {var msg;if (!("stack" in exception)) {msg = "No
stack trace available.\n" + exception;} else {msg =
exception.stack;}alert("Page Speed Activity encountered an error:\n" +
msg);}),(function () {return fn.apply(context,
arguments);}),-9)@chrome://activity/content/ui.js:186
(-9)@chrome://activity/content/base.js:902

What version of Firefox are you using?  From the 'Help' menu, select 'About
Mozilla Firefox' to get the version.
Firefox 3.5

What version of Firebug are you using?  From the 'Tools' menu, select 'Add-
ons', and click on 'Extensions'.  Firebug and its version should be listed.
1.4.0b7

What version of Page Speed are you using?  Follow the procedure to get the
Firebug version, and look for 'Page Speed' in the list of extensions.
1.0.1.1

What operating system are you using?
Windows XP Pro SP3

Please provide any additional information below.

Original issue reported on code.google.com by ylev...@gmail.com on 13 Jul 2009 at 1:43

firstred / page-speed

Can not properly record activity due to error "event start exceeds event end" #94