Tmux, change window pane by mouse click

You can jump directly to a pane by typing pane's index while it is showed by display-panes command.

From man tmux:

display-panes [-t target-client]
                   (alias: displayp)
             Display a visible indicator of each pane shown by target-client.
             See the display-panes-time, display-panes-colour, and
             display-panes-active-colour session options.  While the indicator
             is on screen, a pane may be selected with the ‘0’ to ‘9’ keys.

Or instead of typing command, you can use:

C-b q

• C-b send prefix key
• q display panes indexes

Add this to your ~/.tmux.conf:

set-option -g default-shell /bin/bash
unbind Up     
unbind Down   
unbind Right   
unbind Left  
bind Up run-shell "if [ $(tmux display-message -p '#{pane_at_top}') -ne 1 ]; then tmux select-pane -U; fi"
bind Down run-shell "if [ $(tmux display-message -p '#{pane_at_bottom}') -ne 1 ] ; then tmux select-pane -D; fi"
bind Right run-shell "if [ $(tmux display-message -p '#{pane_at_right}') -ne 1 ]; then tmux select-pane -R; fi"
bind Left run-shell "if [ $(tmux display-message -p '#{pane_at_left}') -ne 1 ]; then tmux select-pane -L; fi"

Basically, this should run with tmux versions 2.6 + (after which they added the pane_at_top, pane_at_bottom, pane_at_left, pane_at_right environment variables. For tmux < v2.6, I'm not entirely sure how you could implement this.

Further more, if you want to launch a custom-shell, do it through set-option -g default-command fish (or zsh or csh or whatever). As an alternative, if you want to use a non-bash shell as your tmux default shell, set it as such (set-option -g default-shell) and then you can code out the logic above in the shell script of your choice. However, (as was in my case) using certain shells doesn't give you the convenience of one-liner if commands (or it might just be I don't know enough about certain shells, or maybe multiple lines do work in run-shell.

Source: github Issues thread that I started