Are you a Firefox user who regularly cleans the Firefox history and other traces like downloads from the web browser’s memory? Do you think that these information are really gone and cannot be recovered because you have deleted them? You might want to think again as it is usually possible to recover data on computer systems even if it has been deleted by the user. There are exemptions to the rule. If the free space of the hard drive has been overwritten by software to clean it of data traces then recovery is not possible. The same is true if Firefox was executed from a read only device.
Firefox 3 History Recovery helps in all other cases. It is a command line tool that can analyse uncompressed disk images to discover traces of the four SQLite tables moz_places, moz_historyvisits, moz_formhistory and moz_downloads. What the recovery tool can return are therefor the visited urls, the form history and the downloads.
Firefox 3 History Recovery is a forensic tool and therefor not designed with usability in mind. It can only be executed from the command line and the biggest problem that users face is that they need to create a disk image for this process. The developer mentioned a few tools that can be used to create those disk images: winhex, ftk imager and dcfldd.

The program itself is easy to use in comparison. All the user needs to do is to enter the command
ff3hr -i
to start the recovery process. The command line tool will create four new text documents in its directory that will contain the information found on the disk image. Firefox 3 History Recovery is an Open Source software program that is available at the Sourceforge website.

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So, how DOES a user of Firefox clean up a (non) portable history?
Mike, you need to clean the unused disk space with a tool like Eraser (which works great unless you have SSDs).