I would like to adopt the Autogroup plugin, which is stuck at support for Moodle 2.8 only. I have tried to contact the original developer but haven't had any response. Is there any procedure in place for when a plugin is left in limbo, neither supported nor put up for adoption?
That's a good question. Coincidentally I was just today dealing with a similar case and we in HQ concluded that we need a new policy of how long we should wait for a reply from inactive maintainer before we can start considering the plugin as orphaned and put it for adoption on behalf of the maintainer.
Please see MDLSITE-5354 for details. I am going to report your case there for reference. Thanks!