Input sluggish after upgrade to debian 13/trixie

[kaHaleMaKai]

Describe the bug

Since upgrading today, kitty reponds very sluggishly, often times the screen is updated after every other key stroke (or mouse click). When hitting enter after a command, the output is shown only after I hit another key, e.g. the sudo prompt does not appear without pressing another key.

Besides, when I move between virtual desktops, existing kitty windows tend to show input from another application from the previously visited virtual desktop.

When using any other terminal like xterm, it just works. Important: before upgrading to debian 13 today, kitty has worked smoothly as always.

I have tested against versions

• 0.25.3
• 0.25.5 (packaged w/ debian 13)
• 0.27.1

To Reproduce

Unfortunately, I cannot offer an example for reproducing this. I haven't checked, whether this is a generic error in debian 13.

Screenshots If applicable, add screenshots to help explain your problem.

Environment details

kitty 0.28.1 (da1276d84a) created by Kovid Goyal
Linux lanai 6.1.0-9-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.1.27-1 (2023-05-08) x86_64
Debian GNU/Linux 12 lanai /dev/tty

Running under: X11
Frozen: True
Paths:
  kitty: /home/lars/local/kitty/bin/kitty
  base dir: /home/lars/local/kitty/lib/kitty
  extensions dir: /home/lars/local/kitty/lib/kitty-extensions
  system shell: /usr/bin/zsh
Loaded config files:
  /etc/xdg/kitty/kitty.conf
  /home/lars/.config/kitty/kitty.conf

Config options different from defaults:
bell_on_tab                
clipboard_control          ('write-clipboard', 'write-primary')
close_on_child_death       True
confirm_os_window_close    0
cursor                     None
cursor_blink_interval      0.0
cursor_text_color          None
editor                     nvim
enable_audio_bell          False
font_family                Hack
font_size                  9.0
hide_window_decorations    1
initial_window_height      (1080, 'px')
initial_window_width       (1920, 'px')
modify_font:
    cell_height 1
    cell_width 0
remember_window_size       False
repaint_delay              6
scrollback_lines           50000
select_by_word_characters  -A-Za-z0-9,./?%&#:_=+@~[]{}()
shell_integration          frozenset({'no-cursor'})
single_window_margin_width FloatEdges(left=-1000.0, top=-1000.0, right=-1000.0, bottom=-1000.0)
tab_bar_style              hidden
tab_title_template         {title}
update_check_interval      0.0
window_alert_on_bell       False
window_border_width        (1.0, 'pt')
Added shortcuts:
    shift+down →  scroll_line_down
    shift+end →  scroll_end
    shift+home →  scroll_home
    shift+page_down →  scroll_page_down
    shift+page_up →  scroll_page_up
    shift+up →  scroll_line_up
Changed shortcuts:
    kitty_mod+0 →  change_font_size all 0
    kitty_mod+x →  kitten hints
Colors:
    background                 #101000   
    color0                     #101000   
    color1                     #a4a000   
    color10                    #b27200   
    color11                    #d96000   
    color12                    #8eda00   
    color13                    #cea900   
    color14                    #f9b600   
    color15                    #ded39f   
    color2                     #b27200   
    color3                     #d96000   
    color4                     #8eda00   
    color5                     #cea900   
    color6                     #f9b600   
    color7                     #ded39f   
    color8                     #9b936f   
    color9                     #a4a000   
    foreground                 #ded39f   

Important environment variables seen by the kitty process:
    PATH                                /home/lars/local/appimages:/home/lars/local/rofi-pass:/home/lars/git/kahalemakai/rofi-menus:/home/lars/bin:/home/lars/bin/ansible:/home/lars/bin/gcp-subcommands:/home/lars/bin/git-lab-commands:/home/lars/bin/gradlewim:/home/lars/bin/.kubectl:/home/lars/bin/kubectx:/home/lars/local/avro/bin:/home/lars/local/avro-tools/bin:/home/lars/local/backup-my-phone/bin:/home/lars/local/bin:/home/lars/local/fzf/bin:/home/lars/local/git-extra-commands/bin:/home/lars/local/glab/bin:/home/lars/local/helm/bin:/home/lars/local/idea-IC-223.8214.52/bin:/home/lars/local/kitty-0.28.1/bin:/home/lars/local/kitty/bin:/home/lars/local/kitty.BK/bin:/home/lars/local/luarocks-5.3/bin:/home/lars/local/neovim-qt/bin:/home/lars/local/qtile-test/bin:/opt/spark/current/bin:/home/lars/.gem/ruby/3.0.0/bin:/home/lars/.gem/ruby/2.3.0/bin:/home/lars/.cargo/bin:/opt/paloaltonetworks/globalprotect:/home/lars/.local/bin:/bin:/usr/bin:/usr/ucb:/usr/local/bin:/usr/lib/lightdm/lightdm:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/home/lars/.local/bin
    LANG                                en_US.UTF-8
    SHELL                               /usr/bin/zsh
    GLFW_IM_MODULE                      ibus
    DISPLAY                             :0
    USER                                lars
    XDG_SEAT                            seat0
    XDG_SESSION_TYPE                    x11
    XDG_SEAT_PATH                       /org/freedesktop/DisplayManager/Seat0
    XDG_SESSION_CLASS                   user
    XDG_SESSION_ID                      2
    XDG_SESSION_PATH                    /org/freedesktop/DisplayManager/Session0
    XDG_RUNTIME_DIR                     /run/user/1000
    XDG_SESSION_DESKTOP                 qtile
    XDG_GREETER_DATA_DIR                /var/lib/lightdm/data/lars
    XDG_VTNR                            7
    XDG_DATA_DIRS                       /home/lars/.local/share/flatpak/exports/share:/var/lib/flatpak/exports/share:/usr/local/share:/usr/share

Additional context

Try to reproduce the problem with kitty --config NONE if you cannot then post a minimal kitty.conf that reproduces the problem. If the problem involves interaction with some other terminal program post a minimal config for that program to reproduce the problem as well.

kitty behaves the same with or without custom config.

I'm using

• debian 13/trixie
• the tiling window manager qtile in version 0.22.1
• a DELL Lattitude 7430
• python 3.11.4 (packaged w/ debian)
• zsh 5.9 (although I get the same behaviour with bash and dash)

I do not see the problem with any other application, which does not mean it is the only program with this issue.

[kaHaleMaKai]

Hi Kovid,

thank you very much for providing kitty, I love it totally!

Please tell me which information you would need, or how I could debug this further.

Thank you so much in advance! Best, Lars

[kaHaleMaKai]

I just found the compositor picom to be related to the issue. When disabling it, kitty works normally. I will check now, whether it is only related to picom, or to the combination of picom and kitty.

[kaHaleMaKai]

As soon as I change the picom backend from glx to xrender, kitty works flawlessly again. I do not have a clue – do you have any idea? I'll close the ticket anyhow.

[kovidgoyal]

No clue, I have never used picom in my life.

[kaHaleMaKai]

If anyone else faces the same issue: I have installed compton from the debian sources as a replacement. It might have slightly different feature sets, but I could use my config as-is.