Where Firefox extensions store data?

I want to write plugin for GNOME Do, that will work with Firefox ext开发者_JS百科ensions data (for example, with URL Alias patterns). I have looked through files in my profile folder (~/.mozilla/firefox/.default/), but haven't found anything related.

Can anybody help me?

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I unzipped the XPI, and it looks like the key data is stored in the preference system under the urlalias branch. This is serialized to disk in the prefs.js. file Each line is a single preference, so it should be pretty simple to parse (you could conceivably use Firefox's XPCOM interface, but that's probably unnecessary).