Features›Modes›Origin mode (DECOM)

Origin mode (DECOM)

Category: modes · Baseline: modern · Tags: DEC Private Modes, VT100 · Specification ↗

ESC [ ? 6 h

DECOM (Origin Mode) changes how cursor positioning works relative to scroll margins. Enable with ESC [ ? 6 h. When active, cursor coordinates are relative to the scroll region rather than the entire screen, and the cursor is confined within the scroll region boundaries. Used by applications that operate within scroll regions to simplify coordinate calculations.

How this is testedautomated
Send \x1b[?6h (DECOM), verify originMode is active, then reset with \x1b[?6l.

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 10 of 12 terminals (83%). Not supported by: Kitty, Terminal.app. Part of the Modern TUI baseline. Notes: Kitty: Not exposed via Python batch bridge.

Supported by 11 of 14 backends (79%)

Terminal Applications

Terminal	Version	Support	Notes
iTerm2	3.6.9	✓ yes	DECRPM: mode reset
Ghostty	1.3.1	✓ yes	DECRPM: mode reset
VS Code		✓ yes
Warp		✓ yes
Cursor		✓ yes
Terminal.app		✗ no

Headless Backends

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

Backend	Version	Support	Notes
Alacritty	0.26.0	✓ yes
vt100.js	0.2.1	✓ yes
vterm	0.2.0	✓ yes
WezTerm	0.1.0-fork.5	✓ yes
xterm.js	5.5.0	✓ yes
Kitty	0.40.0	~ partial	Not exposed via Python batch bridge

← Back to matrix · modes features