CLEO is a Firefox extension that works with FEBE to package any number of extensions/themes into a single, installable .xpi file.

Why? Consider this: I, as an extension developer, have several different Firefox profiles. Whenever I start a new extension, I create a new profile for testing, debugging, etc. In this profile, I like to have a dozen or so developer related extensions installed. With CLEO, I can packaged all these extensions together into a single, installable xpi.

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