Joomla Issue Tracker:
http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemBrowse&tracker_id=8103

Github Issue Tracker:
https://github.com/joomla/joomla-cms/issues?direction=asc&sort=created&state=open

Eye-ball and review all issues for currency where there has been no activity for between 3 and 6 months. Force close issues that appear obviously inactive or unconfirmed. In this case add a polite message such as:

There has been no activity on this issue for more several months. We are closing it. If you think this still needs to be address please open a new issue. Instructions can be found .

If the issue exists on both JoomlaCode and Github (maybe only as a pull request) and is cross-linked, close the JoomlaCode issue and delegate resolving the issue to Github. Copy any information to Github that is appropriate to help closing the issue.

If the issue only exists on JoomlaCode then either create a new one on Github or ask the author to do so (if they do it they get the kudos in any statistical reports).