Facebook Timeline profile has officially switched on to all accounts. So, we can’t change the old profile while deleting the Developer App. Here is the Guide to switch old Facebook profile.

How to Delete Facebook Timeline Profile in Mozilla Firefox with User Agent Switcher Add-on:
- You need to install User Agent Switcher Add-on.
- After Installing the Addon Restart the Firefox.
- See your Navigation bar for User Agent Switcher Add-on Icon. If the Icon is not there then right click on it and Customize it.
- Now right click on the icon and choose Internet Explorer 7 option.

See Also :- How to Disable Facebook Timeline on Google Chrome
Now you successfully learnt to disable the New Facebook Timeline and get back the old facebook profile in Mozilla Firefox.