I’ve been using Tmux since 2013, and I wrote a blog post at that time. I somehow revisited my setup last year, but it was still on macOS (and using iTerm2). In the mean time I switched to Kitty, and I enjoyed using it for over a year and a half or so. It worked well in practice, I could use it on my Macbook and even on an OpenBSD machine. Same configuration, multiple OSs – what else? The only thing that I was really missing was getting notification for new activity in other tabs, session management and keyboard-based copy-pasting.

A few weeks ago, I decided to go back to the defaults (since default settings are often good, you know) and use Gnome terminal, which looks like a great terminal emulator, but without ligature support or multiplexing capabilities. Yet we can manage to get a comfy setup by adding Tmux on top of that. Hence I revised for the third time my Tmux config. I’ve been using Byobu on a remote server last year, but finally it didn’t bring me much more and I could do everything I wanted with Tmux alone. In fact, the only thing I really liked in Byobu was its ability to notify about available updates and reboot info so that my status config file ended up with just those items:

tmux_left="session"
tmux_right="reboot_required updates_available load_average"

Since Byobu can use your screen or tmux config files, most of my settings remained in my .tmux.conf file, and it acted as yet another backend.

I am now using Tmux every day, and it goes as smoothly as when I was using Kitty, except that I now have a few additional optins: I can switch my theme easily thanks to Gnome terminal, and I can manage multiple sessions at the same time. I can also detach the current session and close Gnome terminal, I know I will be able to restore everything afterwards unless I rebooted Ubuntu. Here are the core components of my Tmux setup:

• Enable terminal features: In roder to get 256 color support, underline and undercurl etc., you’ll need to tweak the terminal-related settings. I personally use this:

  set -g default-terminal "tmux-256color"
  set -as terminal-overrides ',xterm*:Tc:sitm=\E[3m'
  

  To enable colored underline and undercurl support, please refer to lsp-colors README.

• You can change the default prefix key, whether you’re a past screen user or a current Emacs addict. I am fine with C-b, but I added a second prefix key since I have an almost dead key next to my Esc keys (Esc and CAPS Lock):

  set-option -g prefix2 œ
  

• You’ll likely need to copy-paste between different Tmux buffers. The combo C-[, <space>, <enter>, C-] is kind of a mess, really. As a workaround, consider allowing Vim keybindings using the following settings:

  bind Y copy-mode
  setw -g mode-keys vi
  bind-key -T copy-mode-vi v send -X begin-selection
  bind-key -T copy-mode-vi 'C-v' send -X rectangle-toggle
  set -g set-clipboard off
  bind-key -T copy-mode-vi y send -X copy-pipe-and-cancel "xclip -i -selection clipboard"
  

  Using these settings, you enter “copy-mode” by hitting <prefix> + Y, then select text using Vim motion (e.g., v2w to select the next two words, or C-v v5hj to select a rectangular block of 5 chars x 2 lines), then copy and paste wherever you want using y and S-C-v. It’s all that simple, once you know it. I spent years tearing my hairs out before I discovered that it can that easy, really.

• Other useful mappings, that you may need to adapt to your own taste: (Some are inspired by Byobu default keybindings.)

  bind Q command-prompt -I "htop" -p "Quick window command: " "new-window '%%'"
  bind R source-file ~/.tmux.conf \; display-message "Reloading config"
  bind Y copy-mode
  bind > swap-pane -D         # swap current pane with the next one
  bind < swap-pane -U         # swap current pane with the previous one
  bind Up resize-pane -U 5    # resize panes using arrow keys
  bind Down resize-pane -D 5
  bind Left resize-pane -L 5
  bind Right resize-pane -R 5
  bind m set -g mouse on \; display "Mouse Mode: on"
  bind M set -g mouse off \; display "Mouse Mode: off"
  bind-key -n F1 list-keys
  bind-key -n F2 new-window
  bind-key -n F3 previous-window
  bind-key -n F4 next-window
  bind-key -n F6 detach-client
  bind-key -n F8 command-prompt "rename-window '%%'"
  bind-key -n M-& selectp -t :.+
  bind-key -n M-$ split-window -h -c "#{pane_current_path}"
  bind-key -n M-! split-window -f -l 15 -c "#{pane_current_path}"
  bind-key -n M-Left previous-window
  bind-key -n M-Right next-window
  bind-key -n M-a select-layout even-vertical
  bind-key -n M-A select-layout even-horizontal
  

• As for general settings, you may want to disable visual notification for activity in other windows but keep track of them more subtly using set -g visual-activity off and setw -g monitor-activity on, reduce <Esc> timing for char codes using set -sg escape-time 0, and automagically renumber window by setting set -g renumber-windows on and, optionally, setw -g allow-rename off if you don’t want your tab/window titles as fullwidth process names.

As for the status bar, it is usually a matter of opinion: I for one do not want to rely on external plugins (I can uptime or date myself in the terminal), and I want a minimalist design. Here we go:

And here is the code:

set -g status-interval 5
set -g status-justify left
set -g status-left ""
set -g status-position top
set -g status-right "#[fg=colour3] ♯#S "
if '! [ -z "$SSH_TTY" ]' 'set -g status-right "#[fg=colour145] #(whoami)@#h #[fg=colour3] ♯#S "'
set -g status-style fg=colour145
set -g window-status-current-format "#[fg=colour11,bg=colour3] #I "
set -g window-status-format "#[fg=colour145] #I "
set -g window-status-separator "#[fg=colour145]"

Finally, beside personal keybindings, here are some useful builtin keybindings I keep using regularly:

• <prefix> + z to zoom in a specific pane (much more convenient than tweaking pane layout, IMHO);
• <prefix> + s or <prefix> + w to get a quick overview of my current sessions and windows;
• <prefix> + o to cycle between panes in current windows (instead of <prefix> + arrow keys);
• <prefix> + ! to convert current pane to a proper window (which is almost the equivalent of :tab split in Vim);
• <prefix> + ) to cycle between existing sessions (technically, this is “move to next session”, but I don’t have that much sessions opened at the same time);
• <prefix> + $ to rename a session but this really is an edge case.

I sometimes want to create a new session and attach the current window to it. Here is how we can do: Create a new session using <prefix> + :new, then <prefix> + :move-window -s #name:#pane, where #name is the name of the current session in which the #pane number is. A typical command is :move-window -s main:2 to move “pane number 2” (from session “main”) to the newly created session.

That’s it! I hope you will enjoy Tmux.