Where's the about box in the Firefox source code?

I search in the Mozilla folder using:

grep -R "About Mozilla Firefox" ./*

but there was no result.

By searching just "about" it prints thousands of lines.

Any idea how to find the about box in the Firefox source开发者_StackOverflow code?

Take a look at the aboutDialog.* files, in source/browser/base/content.

If you want to know how to find the source code in future, the easiest way is to use DOM Inspector; you can inspect the chrome window and thus find out its URL, then you can search MXR for the source file name.