I was working on a straight Actionscript 3 application in Flex Builder and realized one thing I was missing was a way to do a trace. When I write actionscript I use trace all the time, much like I use the alert in javascript to check the value of variables or to see if I am executing a method when I think I am.

I found this firefox addon FlashTracer that allows you to trace a flex actionscript application right in the browser. It allows you to view trace messages in a sidebar or floating window. The installation is like any other Firefox addon, but I did have to go into it's preferences and establish a location for the Flash Player log file. I used the spot the install instructions recommended in my //Library/Preferences/Macromdedia/Flash Player/Logs/flashlog.txt. Also, before installing the addon, make sure you are using Adobe's Debugger version of Flash Player. After I installed the FlashTracer addon and did the preferences, I had to restart Firefox before it would begin to trace my application.