For completeness, I did find a ticket related to this:
http://sourceforge.net/p/tmux/tickets/160/
Apparently F13 was changed to S-F1 in v1.9 so a key binding is no longer
neccessary. I confirmed I can just type "Shift + F1" on my standard
keyboard and F13 is sent.
On 02/27/2015 10:1
Hello,
I recently upgraded from Ubuntu 14.04 LTS to 14.10 and seem to have lost
some functionality in tmux. 14.04 uses tmux 1.8 and 14.10 has 1.9, so I
am guessing that is the issue. I installed tmux 1.8 on my current ubuntu
14.10 machine and can verify that the functionality is back.
I am talkin
