Skip to content

Set Wayland app-id (OSC 176)

Category: extensions · Baseline: rich · Tags: Operating System Commands (OSC) · Specification ↗

ESC ] 176 ; app-id BEL
OSC 176 sets the Wayland window's app-id at runtime. The sequence is ESC ] 176 ; app-id BEL and is specific to foot, the Wayland-native terminal emulator. Wayland window managers use the app-id to group windows, apply per-application rules, and select icons — analogous to WM_CLASS on X11. By exposing app-id setting as an escape sequence, foot lets shell scripts and TUIs differentiate themselves at the compositor level (for example, marking a terminal running a specific TUI so a tiling window manager can place it on a dedicated workspace). No other terminal implements OSC 176; on non-foot terminals the sequence is silently consumed or ignored.
How this is testedpartial
Send OSC 176 ; terminfo-test BEL and verify the terminal consumes the sequence (cursor position unchanged).

The same probe runs against headless backends (via Termless) and real terminal apps (via a daemon launched in each terminal). This lets us distinguish parser correctness from rendering correctness.

Analysis2026-04-06

Supported by all 4 tested terminals — universal adoption. Part of the Rich TUI baseline.

Supported by 8 of 14 backends (57%)

Terminal Applications

TerminalVersionSupportNotes
iTerm23.6.9✓ yes
Ghostty1.3.1✓ yes
VS Code✓ yes
Warp✓ yes
Cursor✓ yes
Terminal.app✓ yes

Headless Backends

Parser correctness only — a means the parser accepts the sequence.

BackendVersionSupportNotes
Alacritty0.26.0? unknown
Kitty0.40.0? unknown
vt100.js0.2.1? unknown
vterm0.2.0? unknown
WezTerm0.1.0-fork.5? unknown
xterm.js5.5.0? unknown