Earlier this month, Angie sent a link to what you might consider as a possible replacement for functionality found useful in the Klokan bounding tool tool.  Chris Garrity and I were very gratified by your responses, and hope you'll find this new tool useful in supporting your work.  We're committed to supporting it in the long term, and welcome your continued input.  There likely will be a few more feature updates in the coming weeks...

https://ngmdb.usgs.gov/extent/

Best regards, and Happy New Year!

Dave Soller