Firefox shell script:
optimize SQLite by running vacuum

Syntax:

firefox-optimize-sqlite-vacuum

Credit: http://ubuntuforums.org/showthread.php?t=1193567

Firefox stores a lot of data, for example bookmarks, in database files. The files are in your profile directory and have the extension .sqlite.

This script looks for sqlite database files in your ~/.mozilla folder, then executes the sqlite vacuum command, which removes stale data.