Mightty
Protocols
Programs control a terminal by writing escape sequences. Mightty supports the VT100 and xterm sequences that programs depend on, and the newer protocols listed on this page.
Images
Mightty supports the kitty graphics protocol.
- Images can be sent inline, or passed as a file, a temporary file or shared memory, in PNG format or as raw pixels.
- Images scroll with the text and can be drawn under or over it.
- Images can be placed relative to each other and can be animated, so
kitten icatplays GIFs. - Unicode placeholders are supported, which lets images display through tmux.
Keyboard
Mightty supports the kitty keyboard protocol with all five of its options. Programs that use it, such as Neovim, Helix, Kakoune and fish, can tell Ctrl-I from Tab and Esc from Alt, and can see when a key is released.
Input methods are supported. The text being composed is drawn at the cursor.
Text
- Widths. Character widths follow Unicode 17. Emoji sequences and combining marks stay in one cell. Mode 2027 is on by default, and a program that counts widths the older way can turn it off.
- Underlines. Single, double, curly, dotted and dashed underlines, in any colour (SGR 58). Editors use these to mark errors and warnings.
- Links. OSC 8 hyperlinks, opened with ⌘-click.
Colours and appearance
| Sequence | What a program can do |
|---|---|
| OSC 4, 10, 11, 12 | Set and read the 16 colours and the default foreground, background and cursor colours. |
| OSC 104, 110 to 112 | Reset those colours. |
| OSC 50 | Set the font family of its pane. The settings screen uses this to preview fonts. |
| OSC 22 | Set the shape of the mouse pointer. |
| OSC 9;4 | Report progress, shown as a thin bar along the top of the pane. |
Clipboard and notifications
- OSC 52 lets a program copy to the clipboard and read from it, including over ssh. By default, copying is allowed and Mightty asks before a program reads the clipboard. The
clipboard-writeandclipboard-readsettings change this. - OSC 9 and OSC 777 notifications mark the pane as needing your attention. See Agents and scripting.
Queries
A program can ask for the cursor position, the terminal's name and version (XTVERSION), and whether a mode is on (DECRQM).
Safety
Output can come from any program, including one on a server you reach over ssh, so Mightty treats all of it as untrusted.
- Titles and commands. Control characters are removed from window titles and command lines.
- Pasting. Mightty asks before pasting text that could run a command: text that contains control characters, or text with a line break when the program hasn't turned on bracketed paste.
- Passwords. Secure Keyboard Entry turns on at password prompts, so other apps can't read what you type.
- Size limits. Images and escape sequences have size limits. An escape sequence over the limit is ignored, not acted on in part.
- Files. A program can ask Mightty to read an image from a file, but only a complete PNG, and Mightty's reply never reveals whether a file exists.