http://kb.mozillazine.org/App.update.channel

 

 

Edit about:config >> app.update.channel and restarting does not work
....since about Fire Fox 1.5 ?!?!?

 

To change your update channel:

1. Close Firefox.
2. Go to the Firefox program directory.
3. Enter defaults\pref
4. Edit channel-prefs.js in Notepad.

Change:

pref("app.update.channel", "release");

to the one you desire. Update channels to choose from:

nightly
aurora
beta
esr
release

Example:

pref("app.update.channel", "beta");

5. Save and exit.
6. Re-open Firefox.