dotfiles/docs/terminal/tmux.mdx

---
title: tmux
description: tmux prefix, bindings, kitty-style window tabs with Nerd Font icons, and resurrect/continuum persistence.
---

Terminal multiplexer. [Ghostty](/terminal/ghostty) runs nothing but tmux, and Ghostty's `ctrl+shift` chords are tmux bindings. tmux is also used through the kitty tmux host and remotely on goliath.

| | |
| --- | --- |
| Source | `dot_config/tmux/tmux.conf`, `dot_config/tmux/tmux-nerd-font-window-name.yml`, `dot_config/tmux/executable_tab-label.sh`, `dot_config/tmux/executable_niri-title.sh`, `dot_config/omarchy/themed/tmux.conf.tpl`, `dot_config/omarchy/hooks/theme-set.d/executable_tmux-tabs` |
| Target | `~/.config/tmux/`, `~/.config/omarchy/` |
| Install | `tmux` in `.chezmoidata/packages.yaml` (pacman, brew) |

tpm is a `git-repo` external in `.chezmoiexternal.toml`, cloned to `~/.config/tmux/plugins/tpm` when missing. `tmux.conf` ends with `run '~/.config/tmux/plugins/tpm/tpm'`. Plugins installed by tpm (`prefix I`) land next to it and are ignored by chezmoi.

## Options

The prefix is `ctrl+space`; `ctrl+b` is `prefix2` (the byte Ghostty sends).

| Option | Value |
| --- | --- |
| `default-terminal` | `tmux-256color`; `RGB` override for every terminal; `clipboard` feature; `extkeys` for xterm-kitty |
| `extended-keys` | `on`, format `csi-u` |
| `base-index` / `pane-base-index` | `1` / `1`; `renumber-windows on` |
| `status-position` | `top`, `status-interval 5` |
| `allow-passthrough` / `set-clipboard` / `mouse` / `focus-events` | `on` |
| `update-environment` | `TERM` and `TERM_PROGRAM` appended, so programs see the outer terminal (Ghostty/kitty) |
| `mode-keys` | `vi` |
| `set-titles` | `on`, `#h:#W` |
| `automatic-rename-format` | `#{window_icon} <label>`: Nerd Font icon, then the dynamic label described under [Window tabs](#window-tabs) |
| `history-limit` | `50000` |
| `detach-on-destroy` | `off` (killing a session switches to another instead of detaching) |

These settings are what [yazi](/tools/yazi) needs inside tmux. `allow-passthrough` carries image previews through to the terminal, `set-clipboard` copies paths via OSC 52, and the two environment variables let yazi detect the outer terminal's graphics support. Nothing binds `M-[`: tmux would read the `ESC [` that starts yazi's terminal-query replies as that key and break yazi's capability detection.

## Keybindings

`prefix ?` opens all of them in a popup (`omarchy-menu-tmux-keybindings`).

| Key | Action |
| --- | --- |
| `prefix q` | Reload config |
| `prefix /` | Copy mode, then search upward |
| `prefix o` | tmux-sessionx: fuzzy-find, switch to, create, rename (`ctrl-r`), or kill (`alt-backspace`) sessions, with a preview |
| `prefix h` / `prefix v` | Split below / right, pane cwd |
| `prefix x` | Kill pane |
| `M-Enter` / `M-S-Enter` / `M-Escape` (no prefix) | Split below / split right / kill pane |
| `C-M-arrows` / `C-M-S-arrows` (no prefix) | Focus pane / resize pane by 5 |
| `prefix c` / `prefix k` / `prefix r` | New window in pane cwd / kill window / rename window |
| `M-1` … `M-9` (no prefix) | Select window 1–9 |
| `M-Left` / `M-Right` (no prefix) | Previous / next window |
| `M-S-Left` / `M-S-Right` (no prefix) | Move window left / right |
| `prefix C` / `prefix K` / `prefix R` | New / kill / rename session |
| `prefix P` / `prefix N`, `M-Up` / `M-Down` | Previous / next session |
| Copy mode `v` / `y` | Begin selection / copy and exit |

## Window tabs

The status line copies kitty's tab bar (`tab_bar_style powerline`, `tab_powerline_style angled`). The current window is an accent-tinted plate with accent text. The other windows use `bg=default` and muted text, so the terminal's transparency shows through them, as with kitty's `tab_bar_background none`. As in kitty, a solid arrow leads into the current window and a thin one sits between two inactive windows. The arrow into the current window is its notch, drawn with the inverse glyph `U+E0D6` in the plate color, which keeps the notch transparent. The session name is an accent pill on the far left (`status-justify left`); its arrow points straight into the first tab, so the pill and tabs read as one chain of arrows. The right side shows `COPY`/`PREFIX`/`ZOOM` flags and the hostname.

Colors are the user options `@tab-bg` (the session pill's text), `@tab-fg`, `@tab-active-bg`, and `@tab-active-fg`. `tmux.conf` sets cyberdream defaults, then sources `~/.local/state/omarchy/current/theme/tmux.conf` if it exists. Omarchy renders that file from `~/.config/omarchy/themed/tmux.conf.tpl`, using the same derivation as the kitty tab bar (active background = accent mixed 20% into background). On a theme change, the `theme-set.d/tmux-tabs` hook re-sources it into the running server, so the tabs recolor like kitty's.

### Tab labels

Each window reads `<index> <icon> <label>`, updating as you work, the same rule as kitty's `tab_bar.py`:

| Pane runs | Label | Source |
| --- | --- | --- |
| `nvim`/`vim`/`hx`/`helix`, editing a file | The file name | The title nvim sets (`<file> \| <org/repo>`, astrocore `custom_title`), read from `#{pane_title}` by the format itself, so a buffer switch relabels the tab immediately |
| Anything else, or an editor with no file | Repo the cwd belongs to (walks up for `.git`); the directory name outside a repo; `~` at home | `tab-label.sh`, run as an async `#()` job. When its output differs from the current name, it re-arms `automatic-rename` so tmux relabels right after a `cd` instead of on the next keystroke |

Labels longer than 27 characters end in `…`. The icon comes from tmux-nerd-font-window-name.

## Plugins

| Plugin | Settings |
| --- | --- |
| `tmux-plugins/tpm` | Plugin manager |
| `tmux-plugins/tmux-sensible` | Defaults |
| `joshmedeski/tmux-nerd-font-window-name` | Fills `#{window_icon}` from `tmux-nerd-font-window-name.yml` |
| `tmux-plugins/tmux-resurrect` | `@resurrect-capture-pane-contents on` |
| `tmux-plugins/tmux-continuum` | `@continuum-save-interval 10`, `@continuum-restore on` |
| `omerxx/tmux-sessionx` | `@sessionx-bind o`; `@sessionx-zoxide-mode on` (a query that matches no session is resolved through zoxide into a new session); `@sessionx-fzf-builtin-tmux on` (`fzf --tmux` popup; needs fzf ≥ 0.53, bat for previews) |

### Persistence

resurrect saves sessions, windows, panes, cwds, pane contents, and a default set of programs (nvim, less, man, …). Keys: `prefix C-s` saves, `prefix C-r` restores. continuum saves automatically every 10 minutes. When a tmux server starts and no other tmux server is running, continuum restores the last save. In practice that means the first Ghostty window after login or a reboot.

## tmux-nerd-font-window-name.yml

`show-name: false`, because `automatic-rename-format` supplies the label. The icon sits on the left, with a fallback icon and a blank multi-pane icon. Icons are defined for `mprocs`, `mm`, `macmon`, `make`, `zsh`, `nvim`, `devbox`, `psql`, `yazi`, `lazygit`, `gh`, `tv`, `docker`, `bun`, `node`, `npm`, `pnpm`, `go`, `bunx`, and `claude`. The plugin parses the YAML with awk and does not interpret `\U` escapes, so the glyphs are literal characters.

## niri-title.sh

Installed only on Linux `desktop`/`laptop` roles (gated in `.chezmoiignore.tmpl`). Given the pane command, path, tty, and title, it prints a context segment for the window title read by [Niri](/desktop/niri). It picks the first match:

1. `ssh`/`mosh-client`/`autossh`/`et`: the remote target.
2. `nvim`/`vim`: the pane title (current file).
3. Git repo: directory name and branch.
4. Otherwise the cwd basename.

`tmux.conf` does not currently call the script; its title string is `#h:#W`.