We can scroll tmux output with C-b [ by default, and it provides vim like key binding.

However, some bindings are different from my customized vim.

So I add some scripts and settings to open tmux output with Vim (or any other text editor).

Fortunately, tmux has a nice command capture-pane!

#!/bin/bash

# $HOME/bin/vim-edit-tmux-output

file=`mktemp`.sh
tmux capture-pane -pS -32768 > $file
tmux new-window -n:mywindow "vim '+ normal G $' $file"

chmod +x $HOME/bin/vim-edit-tmux-output

# $HOME/.tmux.conf

setenv -g PATH "$HOME/bin:$PATH"
set-option -g history-limit 20000

bind-key C-e run-shell "vim-edit-tmux-output"

Then press C-b C-e and you can open your tmux output!

Another nice feature is that tmux automatically closes the new pane for Vim after quiting vim.