Ghostty and tmux's extended-keys

[gpakosz]

Hello,

With iTerm2, with default settings, I can use the following bindings in my tmux configuration:

set -g extended-keys on
bind -r C-S-H swap-window -t -1 \; select-window -t -1  # swap current window with the previous one
bind -r C-S-L swap-window -t +1 \; select-window -t +1  # swap current window with the next one

And I can swap windows' position by doing: CTRL + B, keep CTRL pressed, start pressing SHIFT, and then press H or L.
Which will move the current window to the left or to the right in the window list.

This doesn't work in Ghostty.
I've seen #5924 but it's about Neovim.
Here, what doesn't work is tmux itself not reacting to CTRL + SHIFT + <letter> bindings.

Does someone have a solution please?

(I tried with both tmux 3.5a and tmux next-3.6)

[gpakosz]

I just noticed that if I want it to work in Ghostty, I need to use C-S-h/C-S-l instead of C-S-H/C-S-L:

bind -r C-S-h swap-window -t -1 \; select-window -t -1  # swap current window with the previous one
bind -r C-S-l swap-window -t +1 \; select-window -t +1  # swap current window with the next one

I'm not sure who's in the wrong between iTerm2 and Ghostty.

[gpakosz]

Hello @mitchellh 👋

Pinging you here as I reached out to tmux authors.

When pressing Control + Shift + H or Control + Shift + L, Ghostty behaves differently from iTerm2 and Xterm.

In Ghostty

• Press Control + Shift + H → ^[[27;5;72~
• Press Control + Shift + L → ^[[27;5;76~

In iTerm2 and Xterm

• Press Control + Shift + H → ^[[27;6;72~
• Press Control + Shift + L → ^[[27;6;76~

I wanted to report this as a bug but it seems I first need this discussion to get traction then approval?

[mitchellh]

Fantastic. I've verified this, found the bug, wrote a test, and PRed the fix: #9289.

Thank you.