Making ‘new line’ in Claude Code in the Kitty-terminal

Setting the scene

In my daily life, I use: Kitty as my terminal emulator and Tmux in it, which is a terminal multiplexer. For people who aren’t familiar with it, I would describe it like this:
Kitty being a standard terminal emulator (like ‘Terminal’, ‘Iterm’).
And Tmux being this application that I open up in Kitty and do everything inside. Tmux has a nice way of being more Keyboard-minded, with possibility to make tabs, windows and sessions in a better way.

I’m used to having all terminal-things happening in Tmux in tabs and splits and windows; and I love it!

My paper cut

Claude Code runs in your terminal emulator. But there is a bug in Kitty, so you can’t make a new line in Claude Code: Shift+Enter sends the prompt – and not a new line. Even after running: /terminal-setup the issue persists.

It was such a nuisance, that I actually tried having Claude running in iTerm instead, not running Claude with my other terminal commands.
It was close to being fine, but then I just had two terminal applications to maintain and make shortcuts for.

The solution

TL;DR-solution

Put the following in you kitty.conf :

map --when-focus-on title:claude shift+enter send_text normal,application \x0a

Descriptive solution

I decided to try and solve it for Kitty instead.

I found this post: Configuring Kitty Terminal for Claude Code Multi-line Input. Which was close!

If I add this to my ~/.config/kitty/kitty.conf :

map --when-focus-on title:claude shift+enter send_text normal,application \\\n

And opened Claude Code and typed:

Test[ENTER]

then it became:

Test\

… making a newline, but with a redundant backslash with it.

But if I added this instead:

map --when-focus-on title:claude shift+enter send_text normal,application \x0a

Then it works!

Update / Consideration

Maybe I should actually move away from Kitty. It seems to be more in the way, than it is helping me.

All I do happens in Tmux anyway.