Appearance
Highlight foreground (OSC 19)
ESC ] 19 ; spec BELOSC 19 sets or queries the terminal's selection highlight foreground color. The query is
ESC ] 19 ; ? BEL and the terminal responds with the color in X11 rgb:RR/GG/BB format. Setting uses ESC ] 19 ; spec BEL. This is the complement to OSC 17 (highlight background) — together they give applications full control over selection appearance. Fewer terminals support OSC 19 than OSC 17, as some terminals use a fixed or alpha-blended selection foreground. Supported by xterm and foot.How this is testedautomated
Query highlight foreground color with
Query highlight foreground color with
OSC 19 ; ? BEL, verify response matches OSC 19 ; rgb:... pattern via feedCapture.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 3 of 9 terminals (33%). Part of the Rich TUI baseline.
Supported by 3 of 14 backends (21%)
Terminal Applications
| Terminal | Version | Support | Notes |
|---|---|---|---|
| iTerm2 | 3.6.9 | ✓ yes | |
| Terminal.app | ✓ yes | ||
| Ghostty | 1.3.1 | ✗ no | No OSC 19 response |
| VS Code | ✗ no | ||
| Warp | ✗ no | ||
| Cursor | ✗ no |
Headless Backends
Parser correctness only — a ✓ means the parser accepts the sequence.
| Backend | Version | Support | Notes |
|---|---|---|---|
| Alacritty | 0.26.0 | ✗ no | OSC 19 highlight foreground query requires a real display — headless backends have no color palette to query |
| Kitty | 0.40.0 | ✗ no | OSC 19 highlight foreground query requires a real display — headless backends have no color palette to query |
| vt100.js | 0.2.1 | ✗ no | Not implemented — pure TypeScript emulator |
| vterm | 0.2.0 | ✗ no | OSC 19 highlight foreground query not implemented in vterm.js |
| WezTerm | 0.1.0-fork.5 | ✗ no | OSC 19 highlight foreground query requires a real display — headless backends have no color palette to query |
| xterm.js | 5.5.0 | ✗ no | OSC 19 highlight foreground query requires a real display — headless backends have no color palette to query |