Terminal compatibility

jOtter works in any terminal with true colour and mouse support, which today is nearly all of them. What differs is how images look and whether modified keys like Shift+Enter work. Terminal setup explains both.

Terminal	Images	`Shift`+`Enter`	Notes
kitty	kitty graphics	yes	Recommended.
Ghostty	kitty graphics	yes
foot	sixel	yes
WezTerm	iTerm2 protocol	with `enable_kitty_keyboard = true`
Alacritty	half-blocks	yes	No image protocol.
tmux (inside kitty)	the outer terminal’s, with `allow-passthrough on`	no	tmux doesn’t forward the keyboard protocol.
Konsole, GNOME Terminal, xterm	not tested yet	not tested yet

These results come from jOtter’s own detection in each terminal (kitty 0.49, Ghostty 1.3, foot 1.27, WezTerm 2026-03, Alacritty 0.17, tmux 3.6), with default settings. The docs’ recording rig checks them again whenever it runs. Run jOtter with --log to see what it detects in yours: the log’s terminal: line names the image protocol, the cell size and the keyboard protocol.

Half-blocks means images are drawn with Unicode characters at two pixels per cell. Plots stay readable, but fine detail and small text are lost.

Shift+Enter: no means the terminal doesn’t use the kitty keyboard protocol. Use r (run and advance) and Space (run in place) instead.

Gallery

The same notebook in each terminal:

jOtter in kitty: a sharp plot and rendered math — kitty

jOtter in Ghostty: a sharp plot and rendered math — Ghostty

jOtter in foot: a sharp plot (sixel) and rendered math — foot

jOtter in WezTerm: a sharp plot (iTerm2 protocol) and rendered math — WezTerm

jOtter in Alacritty: the plot and math drawn with half-block characters — Alacritty (half-blocks)

Known quirks

Changing the font size (terminal zoom) makes jOtter re-render every cell for the new cell size. Output scroll positions reset and images are sent to the terminal again.
The help screen (?) needs about 33 rows; in shorter terminals it is cut off.
If jOtter is killed with kill -9, the terminal isn’t restored. Run reset to fix it. In kitty, leftover images are cleared the next time jOtter starts.

Using a terminal not listed here? Please report how it works, with the terminal: line from a --log run, so this table can include it.