Make Screenshots of Whole Web Pages Without an Extension

Mozilla has added a Command Line for developers to Firefox Nightly and Aurora. To activate it, do the following steps:

1. Go to about:config.
2. Search for devtools.toolbar.enable and double-click to enable that.
3. Restart the browser.
4. Press Ctrl + Shift + V to open the developer toolbar with the command line.

(I suppose it will be enabled and available on the Tools menu by default in Firefox 16 – 17.)

With this command line, you can make a screenshot of a whole web page by typing:

screenshot filename.png 0 true