Actionscript – See trace() of Flash when running in browser


What's an easy way to see the trace() output of Flash/Flex movies when running in any browser?

Best Solution

Download and install the content debugger version of Flash Player.

Enable trace logging (official guide) by adding an mm.cfg file:



Where to save mm.cfg depends on the OS:

  • Mac OS X: /Library/Application Support/Macromedia
  • Linux: /home/user name

The log file, flashlog.txt, can be found at:

  • Windows 95/98/ME/2000/XP: C:\Documents and Settings\username\Application Data\Macromedia\Flash Player\Logs
  • Windows Vista: C:\Users\username\AppData\Roaming\Macromedia\Flash Player\Logs
  • Mac OS X: /Users/username/Library/Preferences/Macromedia/Flash Player/Logs/
  • Linux: /home/username/.macromedia/Flash_Player/Logs/

Optionally, you can install the Firefox add-on FBTracer which displays the trace output in a Firebug panel.