Appearance and themes

Choose how the tmux-ide app looks: follow your terminal, force dark or light, or pick one of 22 theme presets. One setting colors every part of the app, from Home and the sidebar to pane headers, dialogs and terminal panes.

Choose a theme

Open Commands (F5) → Appearance…. The picker lists System · follow terminal, Dark, Light and the theme presets below.

A switch repaints every part of the app at once. The choice is saved to theme.mode and theme.preset in ~/.tmux-ide/config.json.

How System mode detects light or dark

New or unset appearance settings follow the terminal (system). Saved light, dark, and named theme choices stay selected. System mode uses the terminal's reported default background and foreground. ANSI black and white are palette colors, so a partial palette reply does not decide whether the canvas is light or dark. If color queries are unavailable, terminal mode notifications still update the app using built-in defaults.

Theme presets

To set one by hand:

{ "theme": { "preset": "catppuccin" } }

An unknown preset id is ignored. Theme presets color the app; the tmux chrome uses its own theme.accent, theme.status and theme.glyphs tokens. To color one workspace's tmux panes from .tmux-ide/workspace.yml, see per-session theme.

Terminal panes

Terminal panes follow the selected appearance: default foreground/background and standard ANSI colors (slots 0–15) use the theme palette. System appearance uses detected host ANSI colors where available. Named themes derive basic colors from their semantic palette, including status and accent colors.

Automatic contrast

Automatic contrast correction is enabled by default for every appearance. It checks text against its rendered background across the app, including menus, syntax previews, and applications inside terminal panes. Low-contrast text is adjusted for readability; already readable color pairs stay unchanged.

Correction also covers explicit RGB colors and the extended 256-color palette (slots 16–255). Applications keep their own backgrounds. Selecting a light theme does not force an application's explicitly dark background to become light.

In Appearance, click Contrast or press Ctrl+A to turn correction off and preserve the original foreground colors after theme palette mapping. The setting is saved as theme.automaticContrast in the app configuration. Theme previews and contrast changes apply immediately; canceling Appearance restores the previous settings.

Correction targets the 4.5:1 text contrast ratio for opaque text color pairs. Dim text uses explicit subdued colors so terminal-specific dimming cannot undo the correction. Concealed text, blank cells, block/shade and braille graphics, and unresolved transparent colors are left alone. The diagnostic console overlay is outside the correction pass. This improves text readability; it is not a claim of complete accessibility compliance.

Corrections are cached with a fixed size limit. Each frame uses perceptual lightness correction for up to 128 new low-contrast pairs; additional new pairs use a cheaper verified color blend. This bounds expensive work when applications produce thousands of different colors.

Terminal environment

Fresh sessions advertise:

TERM=tmux-256color
COLORTERM=truecolor
COLORFGBG=15;0

NO_COLOR is removed for newly launched shells. Programs that were already running retain the environment with which they started.

Appearance changes repaint existing terminal content, including scrollback and reverse-video text. They do not restart panes or change running programs' environment or their own theme settings.

See also

• Configuration — the theme settings
• tmux chrome — status-bar colors and glyphs
• App tour — the views a theme colors