EXTRA is an extension characteristic of a tool called Google BreakPad. It is a software solution that allows you to report errors and application failures. Google BreakPad is most often associated with the popular Mozilla Firefox web browser.

EXTRA are files that are used to store the crash log generated by Google BreakPad for the Mozilla Firefox application. Such a file is generated when the browser crashes. The data from the EXTRA file can help identify the causes of such a failure. EXTRA is a plain text file.