Maybe a sub of the extensions forum, devoted entirely to deciphering what certain inadequately documented (and unsupported) extensions actually do.
Maybe it could work something like this -- when someone comes across an extension that maybe sounds intriguing, they take one for the team and install it, just to see what it does. then they post the results of their investigation to the forum for others to take note.
On the flip-side people could also post requests -- maybe if they can't figure it out themselves or don't have the time.
This is inspired by several extensions I've seen in recent months, my all-time favorite being one headlined "contaolinks", with the ever-so-insightful description of "contaolinks". Really.
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