Kitty Terminal: Send_key Inconsistency
Hey guys! 👋 I've been wrestling with a weird issue in kitty terminal, and I wanted to see if anyone else has bumped into it. Specifically, it has to do with the send_key action, which seems to behave differently between kitty versions 0.43.1 and 0.44.0. Let's dive in! 👇
The Bug: send_key Fails in Version 0.44.0
So, here's the deal: I've got a config setting in my kitty.conf file that looks like this. It's designed to clear the terminal screen and then trigger a shortcut in my shell (fish, in this case). 🐠
map ctrl+l combine : clear_terminal reset active : send_key alt+r
In kitty version 0.43.1, everything works like a charm. When I hit Ctrl+L, the screen clears, and then the alt+r shortcut is sent to the fish shell. This triggers the shell to redraw the prompt as expected. 👍
However, in version 0.44.0, things go sideways. The screen still clears, but instead of executing the alt+r shortcut, I get the characters ^[r printed on the screen, and nothing else happens. It's like kitty isn't properly interpreting the send_key command anymore. 😒
This inconsistency is a real bummer because it breaks some of my workflow. Any ideas what might be causing this, or if there's a workaround? 🤔
To Reproduce the Bug
If you want to see this firsthand, here’s how you can reproduce the issue:
- Install kitty 0.44.0: Make sure you have the latest version installed.
- Configure kitty.conf: Add the mapping described above to your
kitty.conffile. - Open kitty: Launch your kitty terminal.
- Trigger the command: Press
Ctrl+Lin the terminal. - Observe the behavior: You should see the
^[rcharacters instead of the shortcut being executed. 🧐
Additional Information to Consider
I've included some environment details below that might be helpful for diagnosing the problem. If you spot anything that stands out, let me know! 💡
Environment details
I hope this helps us get to the bottom of this issue, and thanks for taking the time to read through it, folks! 🙏
Environment Details
Here's a breakdown of my system setup. Perhaps there's something here that could provide a clue:
kitty 0.44.0 created by Kovid Goyal
Linux archlinux 6.12.57-1-lts #1 SMP PREEMPT_DYNAMIC Sun, 02 Nov 2025 15:08:33 +0000 x86_64
Arch Linux 6.12.57-1-lts (/dev/tty)
Running under: Wayland (kwin 6.5.2) missing: color-manager
OpenGL: '4.5 (Core Profile) Mesa 25.2.6-arch1.1' Detected version: 4.5
Frozen: False
Fonts:
medium: Sarasa-Fixed-SC-Nerd-Font-Regular: /usr/share/fonts/sarasa-gothic-nerd-fonts/sarasa-regular-nerd-font.ttc:4
Features: ()
bold: Sarasa-Fixed-SC-Nerd-Font-SemiBold: /usr/share/fonts/sarasa-gothic-nerd-fonts/sarasa-semibold-nerd-font.ttc:4
Features: ()
italic: Sarasa-Fixed-SC-Nerd-Font-Italic: /usr/share/fonts/sarasa-gothic-nerd-fonts/sarasa-italic-nerd-font.ttc:4
Features: ()
bi: Sarasa-Fixed-SC-Nerd-Font-SemiBold-Italic: /usr/share/fonts/sarasa-gothic-nerd-fonts/sarasa-semibolditalic-nerd-font.ttc:4
Features: ()
Paths:
kitty: /usr/bin/kitty
base dir: /usr/lib/kitty
extensions dir: /usr/lib/kitty/kitty
system shell: /usr/bin/fish
System color scheme: light. Applied color theme type: none
Loaded config files:
/home/cc/.config/kitty/kitty.conf
Config options different from defaults:
allow_remote_control yes
clipboard_control ('write-clipboard', 'write-primary', 'read-clipboard', 'read-primary')
cursor_text_color None
enabled_layouts ['grid']
font_family family="Sarasa Fixed SC Nerd Font"
font_size 12.0
listen_on unix:/tmp/kitty
shell_integration frozenset({'no-cursor'})
tab_bar_min_tabs 1
tab_bar_style custom
window_padding_width FloatEdges(left=6.0, top=2.0, right=6.0, bottom=2.0)
Added shortcuts:
alt+0 → next_window
alt+9 → previous_window
alt+[ → previous_tab
alt+] → next_tab
alt+f > u → kitty_scrollback_nvim --config ksb_builtin_last_cmd_output, kitty_scrollback_nvim, hints --type hash --program "launch --type=overlay select-string-operation.sh", hints --type word --program "launch --type=overlay select-string-operation.sh", hints --type line --program "launch --type=overlay select-string-operation.sh", hints --type path --program "launch --type=overlay select-path-operation.sh", hints
alt+i → [--when-focus-on=var:in_editor]no-op, scroll_line_up
alt+j → [--when-focus-on=var:in_editor]no-op, scroll_to_prompt -1
alt+k → [--when-focus-on=var:in_editor]no-op, scroll_line_down
alt+l → [--when-focus-on=var:in_editor]no-op, scroll_to_prompt 1
alt+o → [--when-focus-on=var:in_editor]no-op, scroll_end
alt+page_down → [--when-focus-on=var:in_editor]no-op, scroll_page_down
alt+page_up → [--when-focus-on=var:in_editor]no-op, scroll_page_up
alt+super+, → debug_config
alt+u → [--when-focus-on=var:in_editor]no-op, scroll_home
ctrl+0 → goto_tab 10
ctrl+1 → goto_tab 1
ctrl+2 → goto_tab 2
ctrl+3 → goto_tab 3
ctrl+4 → goto_tab 4
ctrl+5 → goto_tab 5
ctrl+6 → goto_tab 6
ctrl+7 → goto_tab 7
ctrl+8 → goto_tab 8
ctrl+9 → goto_tab 9
ctrl+c → [--when-focus-on=var:in_editor]no-op, copy_and_clear_or_interrupt
ctrl+escape → kitty_shell window
ctrl+f5 → load_config_file
ctrl+l → [--when-focus-on=var:in_editor]no-op, combine : clear_terminal reset active : send_key alt+r
ctrl+p → launch --cwd=current
ctrl+shift+f6 → debug_config
ctrl+shift+l → [--when-focus-on=var:in_editor]no-op, clear_terminal reset active
ctrl+t → new_tab !neighbor
ctrl+v → [--when-focus-on=var:in_editor]no-op, paste_from_clipboard
ctrl+w → [--when-focus-on=var:in_editor]no-op, close_window
shift+alt+0 → move_window_forward
shift+alt+9 → move_window_backward
shift+alt+[ → move_tab_backward
shift+alt+] → move_tab_forward
shift+super+l → [--when-focus-on=var:in_editor]no-op, clear_terminal reset active
super+0 → goto_tab 10
super+1 → goto_tab 1
super+2 → goto_tab 2
super+3 → goto_tab 3
super+4 → goto_tab 4
super+5 → goto_tab 5
super+6 → goto_tab 6
super+7 → goto_tab 7
super+8 → goto_tab 8
super+9 → goto_tab 9
super+c → [--when-focus-on=var:in_editor]no-op, copy_and_clear_or_interrupt
super+f5 → load_config_file
super+l → [--when-focus-on=var:in_editor]no-op, combine : clear_terminal reset active : send_key alt+r
super+p → launch --cwd=current
super+t → new_tab !neighbor
super+v → [--when-focus-on=var:in_editor]no-op, paste_from_clipboard
super+w → [--when-focus-on=var:in_editor]no-op, close_window
Removed shortcuts:
ctrl+shift+tab → previous_tab
ctrl+tab → next_tab
kitty_mod++ → change_font_size all +2.0
kitty_mod+, → move_tab_backward
kitty_mod+- → change_font_size all -2.0
kitty_mod+. → move_tab_forward
kitty_mod+0 → tenth_window
kitty_mod+1 → first_window
kitty_mod+2 → second_window
kitty_mod+3 → third_window
kitty_mod+4 → fourth_window
kitty_mod+5 → fifth_window
kitty_mod+6 → sixth_window
kitty_mod+7 → seventh_window
kitty_mod+8 → eighth_window
kitty_mod+9 → ninth_window
kitty_mod+= → change_font_size all +2.0
kitty_mod+[ → previous_window
kitty_mod+] → next_window
kitty_mod+` → move_window_to_top
kitty_mod+a > m → set_background_opacity default, set_background_opacity 1, set_background_opacity -0.1, set_background_opacity +0.1
kitty_mod+alt+t → set_tab_title
kitty_mod+b → move_window_backward
kitty_mod+backspace → change_font_size all 0
kitty_mod+c → copy_to_clipboard
kitty_mod+delete → clear_terminal reset active
kitty_mod+down → scroll_line_down
kitty_mod+e → open_url_with_hints
kitty_mod+end → scroll_end
kitty_mod+enter → new_window
kitty_mod+escape → kitty_shell window
kitty_mod+f → move_window_forward
kitty_mod+f1 → show_kitty_doc overview
kitty_mod+f10 → toggle_maximized
kitty_mod+f11 → toggle_fullscreen
kitty_mod+f2 → edit_config_file
kitty_mod+f5 → load_config_file
kitty_mod+f6 → debug_config
kitty_mod+f7 → focus_visible_window
kitty_mod+f8 → swap_with_window
kitty_mod+g → show_last_command_output
kitty_mod+h → show_scrollback
kitty_mod+home → scroll_home
kitty_mod+j → scroll_line_down
kitty_mod+k → scroll_line_up
kitty_mod+kp_add → change_font_size all +2.0
kitty_mod+kp_subtract → change_font_size all -2.0
kitty_mod+l → next_layout
kitty_mod+left → previous_tab
kitty_mod+n → new_os_window
kitty_mod+o → pass_selection_to_program
kitty_mod+p > f → kitten hints --type hyperlink, kitten hints --type linenum, kitten hints --type hash --program -, kitten hints --type word --program -, kitten hints --type line --program -, kitten hints --type path, kitten hints --type path --program -
kitty_mod+page_down → scroll_page_down
kitty_mod+page_up → scroll_page_up
kitty_mod+q → close_tab
kitty_mod+r → start_resizing_window
kitty_mod+right → next_tab
kitty_mod+s → paste_from_selection
kitty_mod+t → new_tab
kitty_mod+u → kitten unicode_input
kitty_mod+up → scroll_line_up
kitty_mod+v → paste_from_clipboard
kitty_mod+w → close_window
kitty_mod+x → scroll_to_prompt 1
kitty_mod+z → scroll_to_prompt -1
shift+insert → paste_from_selection
Colors:
active_tab_background #f8f8f2
active_tab_foreground #282a36
background #282a36
color0 #21222c
color1 #ff5555
color10 #69ff94
color11 #ffffa5
color12 #d6acff
color13 #ff92df
color14 #a4ffff
color2 #50fa7b
color3 #f1fa8c
color4 #bd93f9
color5 #ff79c6
color6 #8be9fd
color7 #f8f8f2
color8 #6272a4
color9 #ff6e6e
cursor #f8f8f2
foreground #f8f8f2
inactive_tab_background #6272a4
inactive_tab_foreground #282a36
mark1_background #ff5555
mark1_foreground #282a36
selection_background #44475a
selection_foreground #ffffff
url_color #8be9fd
Important environment variables seen by the kitty process:
PATH /run/user/1000/fnm_multishells/896_1762791177572/bin:/home/cc/.local/share/cargo/bin:/home/cc/.local/share/go/bin:/home/cc/.local/share/pnpm:/home/cc/.local/bin:/usr/local/sbin:/usr/local/bin:/usr/bin:/usr/bin/site_perl:/usr/bin/vendor_perl:/usr/bin/core_perl:/usr/lib/rustup/bin
LANG zh_CN.UTF-8
EDITOR /usr/bin/nvim
SHELL /usr/bin/fish
DISPLAY :0
WAYLAND_DISPLAY wayland-0
USER cc
XDG_RUNTIME_DIR /run/user/1000
XDG_CACHE_HOME /home/cc/.cache
XDG_CONFIG_DIRS /home/cc/.config/kdedefaults:/etc/xdg
XDG_CONFIG_HOME /home/cc/.config
XDG_CURRENT_DESKTOP KDE
XDG_DATA_HOME /home/cc/.local/share
XDG_MENU_PREFIX plasma-
XDG_SEAT seat0
XDG_SEAT_PATH /org/freedesktop/DisplayManager/Seat0
XDG_SESSION_CLASS user
XDG_SESSION_DESKTOP KDE
XDG_SESSION_ID 2
XDG_SESSION_PATH /org/freedesktop/DisplayManager/Session1
XDG_SESSION_TYPE wayland
XDG_STATE_HOME /home/cc/.local/state
XDG_VTNR 2
I've included my system information, including details about my Linux distribution, display server (Wayland), and the configuration of my kitty terminal. I'm hoping this information helps shed some light on the issue. If you need any more details, just let me know! 🤠
Potential Causes and Troubleshooting Steps
Alright, let's brainstorm some potential reasons behind this kitty send_key behavior and some ways we might try to fix it. 🤔
1. Version-Specific Bugs: It's possible that this is a genuine bug introduced in kitty 0.44.0. Sometimes new versions come with unexpected glitches. If this is the case, the best course of action is to report the bug to the kitty developers (like Kovid Goyal, who created kitty), providing them with as much detail as possible (which we've already started!). 🐛
2. Shell Interaction: The way kitty interacts with your shell (fish, in this case) might have changed between versions. The send_key command could be sending the key sequence in a way that fish, or other shells, is not correctly interpreting in the newer version.
3. Key Code Differences: It's remotely possible that the key codes being sent by the send_key action differ slightly between the two versions of kitty. The newer version may be sending a key code that isn't compatible with your shell. This is a stretch, but could cause a discrepancy.
4. Configuration Conflicts: Though less likely, there could be a subtle conflict in your kitty.conf file or other configuration files that affects the send_key command in 0.44.0. Maybe some other setting is interfering with this command.
Troubleshooting Steps:
To troubleshoot, here's what we can try:
-
Test with a Different Shell: See if the problem occurs with other shells, such as bash or zsh. If it works with other shells, that might indicate an issue with how kitty is interacting with fish.
-
Simplify the Command: Create a very basic
send_keycommand to test. For example, try mappingCtrl+Ltosend_key a. If this doesn't work, it indicates the problem may be broader than justalt+r. -
Check Key Codes: Try to find out what key codes kitty is actually sending. You might use a keylogger tool within the terminal or check the kitty documentation to get more precise details.
-
Review Kitty's Changelog: Check the kitty changelog between
0.43.1and0.44.0to see if there are any changes related to key handling or thesend_keyaction. The changelog might give you valuable information. -
Experiment with keymaps: It is possible the keymap of your system interferes with the
send_keyaction. Try to use a different keymap to see if this solves the problem. -
Inspect Kitty Logs: Enable more detailed logging in kitty (if possible) to see what's happening behind the scenes when you trigger
Ctrl+L. This could provide some clues about how thesend_keycommand is being processed.
Conclusion
This is a perplexing issue, and hopefully, we can pinpoint the root cause! If anyone has insights or suggestions, please share. And if you run into this problem too, let me know; it's always good to know we're not alone! 👍
Thanks for reading, and happy terminal-ing, everyone! 🎉