DO NOT uninstall FOF 2.x that's shipped with Joomla!. It's impossible to uninstall for a reason. It's part of Joomla! and some Joomla! features (post-installation messages and Two Factor Authentication) require it. The version reporting problems are due to Joomla! itself. It only updates that information when it is first installed. Subsequent updates do not modify that information, resulting in misleading versions being reported. However, Joomla is not my software and any attempts I've made in fixing it were met with hostility so I won't even bother. Besides, we have terminated our support for FOF 2.x in 2016.
Regarding FOF30 (FOF 3.x, the current stable branch) being reported twice, that's because of a bug in the Joomla! extensions installer. We have always used the same name tag for FOF 3.x. Apparently at some point Joomla! screwed up and created a new database entry in the #__extensions table for the same extension. Since both records point to the same extension, with the same name, therefore the same folder on your site if you try to uninstall either you will break your site. There's nothing you can do because of the way #__extensions is linked to #__assets which is a tree. You can't just remove a record, it would break the #__assets table which in turn would break your site.
So, basically, all of your issues are irrelevant to our software and are caused by Joomla! bugs. Unfortunately, Joomla! is third party software and we cannot provide fixes for it. In fact, if we tried to fix Joomla! in one of our releases that would be a "core hack" which would cause our software to be banned from the Joomla! Extensions Directory. Using our own installer code to avoid the problems caused by Joomla! bugs would also cause our software to be banned from the Joomla! Extensions Directory. So here we are, being forced to live with Joomla's bugs. As I said, over the years I've tried submitting bug fixes but I was met with hostility by people who both lack the technical acumen and real world Joomla! experience to understand the problem and also have the political clout to block integration of the bug fixes. Spending 20' to find and fix a bug and 14 hours trying to convince people that yeah, it's really a bug and yeah, that's how you fix it is a bad use of our time and makes no business sense. So we just try to work around Joomla! bugs when we have to and ignore the ones which are simply annoying but not break anything, like these double records in the database. What can you do...
Nicholas K. Dionysopoulos
Lead Developer and Director
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