Appearance
cmux
App Terminal
Terminal built on libghostty. Inherits Ghostty's complete VT parser and standards compliance.
cmux is a terminal built by the Ghostty project, powered by libghostty — the same terminal emulation library that drives Ghostty. Unlike traditional multiplexers (despite the name), cmux is a full terminal application that inherits Ghostty's complete VT parser, renderer, and standards compliance.
Because cmux links directly against libghostty, it supports the same feature set as Ghostty: kitty keyboard protocol, kitty graphics, sixel, OSC 8 hyperlinks, semantic prompts, and full Unicode with grapheme clustering. Its feature score on terminfo.dev should be nearly identical to Ghostty's.
Feature results inherited from Ghostty — this terminal uses the same underlying engine and is not probed separately.
92%
232 passed · 19 failed of 251 features
Tested: April 10, 2026
Character Sets
| Feature | Support | Notes |
|---|---|---|
| DEC line drawing character set | ✓ yes | |
| DEC Special Graphics | ✓ yes | |
| G0/G1 character set switching | ✓ yes | |
| UTF-8 mode | ✓ yes |
Cursor
| Feature | Support | Notes |
|---|---|---|
| ANSI restore cursor (CSI u) | ✓ yes | |
| ANSI save cursor (CSI s) | ✓ yes | |
| CPL cursor preceding line (CSI F) | ✓ yes | |
| CUD stops at bottom | ✓ yes | cursor at row 119 |
| CUP at screen boundaries | ✗ no | got 119;270, expected within screen bounds |
| CUP with DECOM | ✗ no | got 1;1, expected 5;1 |
| CUU stops at top | ✓ yes | |
| Hide cursor (DECTCEM) | ✓ yes | |
| Cursor horizontal absolute (CHA) | ✓ yes | |
| HPA horizontal position absolute (CSI `) | ✓ yes | |
| Cursor position (CUP) | ✓ yes | |
| Cursor back (CUB) | ✓ yes | |
| Cursor down (CUD) | ✓ yes | |
| Cursor forward (CUF) | ✓ yes | |
| Cursor home | ✓ yes | |
| Cursor up (CUU) | ✓ yes | |
| Cursor next line (CNL) | ✓ yes | |
| Cursor position report (DSR 6) | ✓ yes | |
| Reverse Wrap (Mode 45) | ✓ yes | |
| Save/restore cursor (DECSC) | ✓ yes | |
| Cursor shape (DECSCUSR) | ✓ yes | |
| VPA vertical position absolute (CSI d) | ✓ yes |
Device Status
Editing
| Feature | Support | Notes |
|---|---|---|
| DECCARA — change attrs in rectangle | ✓ yes | sequence consumed |
| DECCRA — copy rectangular area | ✓ yes | sequence consumed |
| DECDC — delete columns (CSI Ps ' ~) | ✓ yes | sequence consumed |
| DECERA — erase rectangular area | ✓ yes | sequence consumed |
| DECFRA — fill rectangular area | ✓ yes | sequence consumed |
| DECIC — insert columns (CSI Ps ' }) | ✓ yes | sequence consumed |
| DECRARA — reverse attrs in rectangle | ✓ yes | sequence consumed |
| DECRQCRA — checksum rectangular area | ✓ yes | sequence consumed |
| DECSACE — select attribute-change extent | ✓ yes | sequence consumed |
| DECSERA — selective erase rectangular area | ✓ yes | sequence consumed |
| Delete characters (DCH) | ✓ yes | |
| Delete lines (DL) | ✓ yes | |
| Insert characters (ICH) | ✓ yes | |
| Insert lines (IL) | ✓ yes | |
| Repeat character (REP) | ✓ yes | |
| SL — shift left (CSI Ps SP @) | ✓ yes | sequence consumed |
| SR — shift right (CSI Ps SP A) | ✓ yes | sequence consumed |
Erase
| Feature | Support | Notes |
|---|---|---|
| Erase character (ECH) | ✓ yes | |
| ED at scroll region boundary | ✓ yes | |
| EL erases with bg color | ✓ yes | |
| Erase line (EL 2) | ✓ yes | |
| Erase to BOL (EL 1) | ✓ yes | |
| Erase to EOL (EL 0) | ✓ yes | |
| Erase above (ED 1) | ✓ yes | |
| Erase screen (ED 2) | ✓ yes | |
| Erase below (ED 0) | ✓ yes | |
| Erase scrollback (ED 3) | ✓ yes | |
| Selective Erase (DECSED) | ✓ yes |
Extensions
Input Protocols
| Feature | Support | Notes |
|---|---|---|
| Button-Event Mouse (1002) | ✓ yes | |
| CSI u Key Encoding | ✓ yes | |
| Kitty click events | ? unknown | |
| modifyOtherKeys | ✓ yes | |
| modifyOtherKeys mode 3 | ✓ yes | |
| Pixel Mouse Reporting (1016) | ✓ yes | SGR pixel mouse mode not tracked by ghostty-web WASM backend |
| urxvt Mouse Reporting (1015) | ✓ yes | |
| X10 Mouse Tracking (9) | ✓ yes |
Modes
Reset
| Feature | Support | Notes |
|---|---|---|
| DECALN screen alignment (ESC # 8) | ✓ yes | |
| Backend reset() method | ✓ yes | cursor at 5;5 after DECSTR |
| Full reset (RIS) | ✓ yes | |
| SGR reset clears attributes | ✓ yes | |
| Soft reset (DECSTR) | ✓ yes |
Scrollback
| Feature | Support | Notes |
|---|---|---|
| Scrollback accumulates | ✓ yes | |
| Alt screen separate scrollback | ✓ yes | |
| DECSTBM constrains scrolling | ✓ yes | |
| DECSTBM reset to full screen | ✓ yes | cursor at row 119 (expected near bottom after DECSTBM reset) |
| Reverse index (RI) | ✓ yes | |
| Scroll down (SD) | ✓ yes | |
| Scroll up (SU) | ✓ yes | |
| Scroll region (DECSTBM) | ✓ yes | |
| Total line count | ✓ yes | Content written to scrollback |
SGR (Text Styling)
Text
| Feature | Support | Notes |
|---|---|---|
| Backspace (BS) | ✓ yes | |
| Basic text rendering | ✓ yes | |
| CBT backward tab (CSI Z) | ✗ no | cursor at col 1, expected 17 |
| CHT forward tab (CSI I) | ✗ no | cursor at col 270, expected 17 |
| Combining characters (0 cols) | ✓ yes | |
| Carriage return | ✓ yes | |
| HTS set tab stop (ESC H) | ✓ yes | |
| Index (IND) | ✓ yes | |
| Line feed | ✓ yes | |
| Next line (NEL) | ✓ yes | |
| Overwrite at cursor | ✓ yes | |
| Reverse Index at Scroll Top | ✓ yes | |
| Tab stops | ✓ yes | |
| TBC clear tab stop (CSI g) | ✗ no | cursor at col 270, expected 1 |
| CJK wide chars (2 cols) | ✓ yes | |
| Emoji wide chars (2 cols) | ✓ yes | |
| Regional indicator flags (2 cols) | ✓ yes | |
| Variation selector 16 (emoji presentation) | ✓ yes | |
| Emoji ZWJ sequences (2 cols) | ✓ yes | |
| Text wraps at width | ✓ yes |
Unicode
| Feature | Support | Notes |
|---|---|---|
| East Asian Ambiguous Width | ✓ yes | width=1 (ambiguous chars vary by terminal/locale) |
| Grapheme Cluster Cursor Movement | ✓ yes | |
| Tab Stops (HT) | ✓ yes | |
| Wide Char at Line Wrap | ✓ yes |