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Emoji wide chars (2 cols)
Tests whether emoji characters correctly occupy two terminal columns. Emoji width handling is more complex than CJK — it involves variation selectors (VS15 for text, VS16 for emoji presentation), zero-width joiners (ZWJ sequences like family emoji), and skin tone modifiers. Terminals frequently disagree on emoji widths, especially for newer Unicode additions.
How this is testedautomated
Write U+1F389 (party popper emoji), verify the cell has
Write U+1F389 (party popper emoji), verify the cell has
wide=true (occupies 2 columns).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 11 of 14 backends (79%)
Terminal Applications
| Terminal | Version | Support | Notes |
|---|---|---|---|
| iTerm2 | 3.6.9 | ✓ yes | |
| Ghostty | 1.3.1 | ✓ yes | |
| VS Code | ✓ yes | ||
| Warp | ✓ yes | ||
| Cursor | ✓ yes | ||
| Terminal.app | ✓ yes |
Headless Backends
Parser correctness only — a ✓ means the parser accepts the sequence.
| Backend | Version | Support | Notes |
|---|---|---|---|
| Alacritty | 0.26.0 | ✓ yes | |
| Kitty | 0.40.0 | ✓ yes | |
| vterm | 0.2.0 | ✓ yes | |
| WezTerm | 0.1.0-fork.5 | ✓ yes | |
| vt100.js | 0.2.1 | ✗ no | Not in VT100/VT220 — ASCII only, no Unicode width |
| xterm.js | 5.5.0 | ✗ no | Headless mode reports emoji as single-width |