Rated 3 out of 5 stars

le wolwerinе ar Meith. 17, 2013 ·

Only 15% of config are covered (without extensions*). I don't think it's that hard to find all description and integrate them to addon.

le Dave G (Forbróir) ar Noll. 13, 2013 ·

True, but then this would be a different extension. I created this to get at the comments left in by the developers that were otherwise inaccessible not to enumerate every one. For the rest, use:
http://kb.mozillazine.org/About:config_entries

If I ever get around to tinkering with this again I'll probably add a context menu option to link to online documentation where available.