Using Nightly Tester Tools
Download Nightly Tester Tools:

There are many things Nightly Tester Tools can do.

A short list on NTT's website gives the following features:

• Extension compatibility fixing
• Titlebar customisation
• Build ID retrieval
• Screenshots
• Breakpad information
• Restoring tabs from previous session
• Leak log analysis

Don’t forget that forcing an incompatible extension to install is risky. There are many cases where Firefox will stop working completely or behave incorrectly because an incompatible extension is being forced to work where the author never intended.

You can use Nightly Tester Tools to override compatibility.
To do that, Install the add on like normal. A window will pop up asking you if you are sure you want to override compatibility. Click "Override Compatibility".
It will be overridden the next time you restart Firefox/Minefield/Gran Paradiso.

If you have the add ons installed, and when you update they are not compatible, go to Tools>Addons.
In the bottom right hand corner, there is a button labeled "Override All Compatibility".
Click it, and the next time you start Firefox/Minefield/Gran Paradiso, the add ons will be active.
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There is also a Nightly Tester Tools option in the "Tools" menu.
The following options are available in the Nightly Tester Tools area of the Tools menu:

• Insert Build ID into textbox

(You can also add a toolbar button for this.)

• Insert list of extensions into textbox
• Take Screenshot
• Open Profile Folder
• Recent Incidents (Which contains a number of your "Recent Incidents")
• Crash Reports Sidebar (Which contains all of the info from the above menu item, in the sidebar)
• Analyze leak log
• Options

In the "Options" menu, you can choose whether you have a custom title ("Mozilla Firefox").
There are a number of things NTT can add to your title:

Everything there is pretty straight forward.

Screenshots:
NTT has the functionality to take a screenshot of any window open in the application.

• Take screenshot on timer
• Crop screenshot to only show the area you need
• Save as jpeg or png
• Upload direct to Imageshack

Session Restore:
You can also selectively restore tabs from your last crashed session.
To do this, go to History->Restore From Last Session.

NTT also has a Leak Guage.
I don't know how to use this, so directly from NTT's website:
"Leak Reporter

The leak guage script is built into NTT. Simply open the leak reporter and tell it where to find your leak log file and you get a full display of leak information.

• Toggle what kinds of leaks to display
• Highlights leaking objects as they are used

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