Unfortunately I often hit F6 instead of F5.
This closes 1/2 of my duel lister and all the tabs that involves (i.e. moves to single lister)
Hitting F6 a 2nd time, opens a the dual lister, but not with the old tabs. Instead the new bottom of the dual lister has a copy of the active tab from the top lister.
How do I get my closed tabs back?