[Hyprland] New window flash black on opening

[Frost-Phoenix]

Describe the bug
When opening a new window in hyprland, the initial background color seems to be black and after a few frames it changes to the right color / background_opacity. So it look like the window is flashing black when opening.
Setting the background_opacity to 1 seems to fix the issue.

Screenshots

Untitled.mp4

Environment details

Kitty debug info

kitty 0.36.4 created by Kovid Goyal
Linux laptop 6.11.2 #1-NixOS SMP PREEMPT_DYNAMIC Fri Oct  4 14:38:57 UTC 2024 x86_64

<<< Welcome to NixOS 24.11.20241006.c31898a (x86_64) - /dev/tty >>>

Run 'nixos-help' for the NixOS manual.

DISTRIB_CODENAME=vicuna
DISTRIB_DESCRIPTION="NixOS 24.11 (Vicuna)"
DISTRIB_ID=nixos
DISTRIB_RELEASE="24.11"
LSB_VERSION="24.11 (Vicuna)"
Running under: Wayland (Hyprland, built from branch  at commit 6ae89940c761d4ed4317df0af29e8df41d472091 ().) missing: blur
OpenGL: '4.6 (Core Profile) Mesa 24.2.2' Detected version: 4.6
Frozen: False
Fonts:
  medium: CaskaydiaCoveNF-Regular: /nix/store/q8y7x6bbmga68h8bhygcy15lk59n22sk-home-manager-path/share/fonts/truetype/NerdFonts/CaskaydiaCoveNerdFont-Regular.ttf:0
          Features: ()
    bold: CaskaydiaCoveNF-SemiBold: /nix/store/q8y7x6bbmga68h8bhygcy15lk59n22sk-home-manager-path/share/fonts/truetype/NerdFonts/CaskaydiaCoveNerdFont-SemiBold.ttf:0
          Features: ()
  italic: CaskaydiaCoveNF-Italic: /nix/store/q8y7x6bbmga68h8bhygcy15lk59n22sk-home-manager-path/share/fonts/truetype/NerdFonts/CaskaydiaCoveNerdFont-Italic.ttf:0
          Features: ()
      bi: CaskaydiaCoveNF-SemiBoldItalic: /nix/store/q8y7x6bbmga68h8bhygcy15lk59n22sk-home-manager-path/share/fonts/truetype/NerdFonts/CaskaydiaCoveNerdFont-SemiBoldItalic.ttf:0
          Features: ()
Paths:
  kitty: /nix/store/vhms4hlp9b9adf93y1hhkcqzl8ciwm74-kitty-0.36.4/bin/kitty
  base dir: /nix/store/vhms4hlp9b9adf93y1hhkcqzl8ciwm74-kitty-0.36.4/lib/kitty
  extensions dir: /nix/store/vhms4hlp9b9adf93y1hhkcqzl8ciwm74-kitty-0.36.4/lib/kitty/kitty
  system shell: /run/current-system/sw/bin/zsh
Loaded config files:
  /home/frostphoenix/.config/kitty/kitty.conf

Config options different from defaults:
active_tab_font_style   (False, False)
background_opacity      0.5
confirm_os_window_close 0
enable_audio_bell       False
font_family             CaskaydiaCove Nerd Font
font_size               15.0
mouse_hide_wait         60.0
scrollback_lines        10000
shell_integration       frozenset({'no-rc'})
tab_bar_style           powerline
tab_title_template      {index}
Added shortcuts:
	alt+1 →  goto_tab 1
	alt+2 →  goto_tab 2
	alt+3 →  goto_tab 3
	alt+4 →  goto_tab 4
Changed shortcuts:
	kitty_mod+left →  no-op
	kitty_mod+right →  no-op
Colors:
	active_tab_background   #7c6f64   
	active_tab_foreground   #fbf1c7   
	background              #1d2021   
	color0                  #3c3836   
	color1                  #cc241d   
	color10                 #b8bb26   
	color11                 #fabd2f   
	color12                 #83a598   
	color13                 #d3869b   
	color14                 #8ec07c   
	color15                 #fbf1c7   
	color2                  #98971a   
	color3                  #d79921   
	color4                  #458588   
	color5                  #b16286   
	color6                  #689d6a   
	color7                  #a89984   
	color8                  #928374   
	color9                  #fb4934   
	cursor                  #bdae93   
	cursor_text_color       #665c54   
	foreground              #ebdbb2   
	inactive_tab_background #3c3836   
	inactive_tab_foreground #fbf1c7   
	selection_background    #d65d0e   
	selection_foreground    #ebdbb2   
	url_color               #458588   

Important environment variables seen by the kitty process:
	PATH                                /nix/store/vhms4hlp9b9adf93y1hhkcqzl8ciwm74-kitty-0.36.4/bin:/nix/store/irkcg78qfr4q5hfmjw8k6w92f8bgb39f-imagemagick-7.1.1-38/bin:/nix/store/q4kwh6ws0s1jd9sq6k4dsr72697bbpjk-ncurses-6.4.20221231-dev/bin:/run/wrappers/bin:/home/frostphoenix/.nix-profile/bin:/nix/profile/bin:/home/frostphoenix/.local/state/nix/profile/bin:/etc/profiles/per-user/frostphoenix/bin:/nix/var/nix/profiles/default/bin:/run/current-system/sw/bin:/nix/store/b74nxf0yn2dzha02mgdxyklaqjaijzqp-binutils-wrapper-2.42/bin:/nix/store/9j787nklwc2zzzczkkbb6v8zxgg8hf2i-pciutils-3.13.0/bin:/nix/store/059q5mjhwq6bkbx4k91p5sg20ds3ji3r-pkgconf-wrapper-2.3.0/bin
	LANG                                en_US.UTF-8
	EDITOR                              nano
	SHELL                               /run/current-system/sw/bin/zsh
	DISPLAY                             :0
	WAYLAND_DISPLAY                     wayland-1
	USER                                frostphoenix
	XDG_CONFIG_DIRS                     /etc/xdg:/home/frostphoenix/.nix-profile/etc/xdg:/nix/profile/etc/xdg:/home/frostphoenix/.local/state/nix/profile/etc/xdg:/etc/profiles/per-user/frostphoenix/etc/xdg:/nix/var/nix/profiles/default/etc/xdg:/run/current-system/sw/etc/xdg
	XDG_SESSION_PATH                    /org/freedesktop/DisplayManager/Session0
	XDG_BACKEND                         wayland
	XDG_SEAT                            seat0
	XDG_SESSION_DESKTOP                 hyprland
	XDG_SESSION_TYPE                    wayland
	XDG_GREETER_DATA_DIR                /var/lib/lightdm-data/frostphoenix
	XDG_CURRENT_DESKTOP                 Hyprland
	XDG_SEAT_PATH                       /org/freedesktop/DisplayManager/Seat0
	XDG_SESSION_CLASS                   user
	XDG_VTNR                            7
	XDG_SESSION_ID                      1
	XDG_RUNTIME_DIR                     /run/user/1000
	XDG_DATA_DIRS                       /nix/store/9xlf3cb1x6d64swl3gc4lwggfxxpzxh6-desktops/share:/home/frostphoenix/.nix-profile/share:/nix/profile/share:/home/frostphoenix/.local/state/nix/profile/share:/etc/profiles/per-user/frostphoenix/share:/nix/var/nix/profiles/default/share:/run/current-system/sw/share

Additional context

hyprland.conf (don't know if this is relevant or not)

monitor=,preferred,auto,auto

animations {
  bezier=fluent_decel, 0, 0.2, 0.4, 1
  bezier=easeOutCirc, 0, 0.55, 0.45, 1
  bezier=easeOutCubic, 0.33, 1, 0.68, 1
  bezier=fade_curve, 0, 0.55, 0.45, 1
  animation=windowsIn,   0, 4, easeOutCubic,  popin 20%
  animation=windowsOut,  0, 4, fluent_decel,  popin 80%
  animation=windowsMove, 1, 2, fluent_decel, slide
  animation=fadeIn,      1, 3,   fade_curve
  animation=fadeOut,     1, 3,   fade_curve
  animation=fadeSwitch,  0, 1,   easeOutCirc
  animation=fadeShadow,  1, 10,  easeOutCirc
  animation=fadeDim,     1, 4,   fluent_decel
  animation=workspaces,  1, 4,   easeOutCubic, fade
  enabled=true
}

decoration {
  blur {
    brightness=1
    contrast=1.400000
    enabled=true
    ignore_opacity=true
    new_optimizations=true
    noise=0
    passes=2
    size=2
    xray=true
  }
  col.shadow=rgba(00000055)
  drop_shadow=true
  rounding=0
  shadow_ignore_window=true
  shadow_offset=0 2
  shadow_range=20
  shadow_render_power=3
}

dwindle {
  force_split=0
  no_gaps_when_only=false
  preserve_split=yes
  pseudotile=yes
  special_scale_factor=1.000000
  split_width_multiplier=1.000000
  use_active_for_splits=true
}

general {
  $mainMod=SUPER
  border_part_of_window=false
  border_size=2
  col.active_border=rgb(98971A)
  col.inactive_border=rgb(928374)
  gaps_in=5
  gaps_out=10
  layout=dwindle
  no_border_on_floating=false
}

input {
  touchpad {
    natural_scroll=true
  }
  float_switch_override_focus=0
  follow_mouse=0
  kb_layout=us,fr
  kb_options=grp:alt_caps_toggle
  mouse_refocus=0
  numlock_by_default=true
  sensitivity=0
}

master {
  new_status=master
  no_gaps_when_only=false
  special_scale_factor=1
}

misc {
  always_follow_on_dnd=true
  animate_manual_resizes=false
  disable_autoreload=true
  disable_hyprland_logo=true
  enable_swallow=true
  focus_on_activate=true
  layers_hog_keyboard_focus=true
  middle_click_paste=false
  new_window_takes_over_fullscreen=2
}

bind=$mainMod, F1, exec, show-keybinds
bind=$mainMod, Return, exec, kitty
bind=ALT, Return, exec, kitty --title float_kitty
bind=$mainMod SHIFT, Return, exec, kitty --start-as=fullscreen -o 'font_size=16'
bind=$mainMod, B, exec, hyprctl dispatch exec '[workspace 1 silent] floorp'
bind=$mainMod, Q, killactive,
bind=$mainMod, F, fullscreen, 0
bind=$mainMod SHIFT, F, fullscreen, 1
bind=$mainMod, Space, exec, toggle_float
bind=$mainMod, D, exec, rofi -show drun || pkill rofi
bind=$mainMod SHIFT, D, exec, webcord --enable-features=UseOzonePlatform --ozone-platform=wayland
bind=$mainMod SHIFT, S, exec, hyprctl dispatch exec '[workspace 5 silent] SoundWireServer'
bind=$mainMod, Escape, exec, swaylock
bind=ALT, Escape, exec, hyprlock
bind=$mainMod SHIFT, Escape, exec, power-menu
bind=$mainMod, P, pseudo,
bind=$mainMod, J, togglesplit,
bind=$mainMod, T, exec, toggle_oppacity
bind=$mainMod, E, exec, nemo
bind=$mainMod SHIFT, B, exec, toggle_waybar
bind=$mainMod, C ,exec, hyprpicker -a
bind=$mainMod, W,exec, wallpaper-picker
bind=$mainMod, N, exec, swaync-client -t -sw
bind=$mainMod SHIFT, W, exec, vm-start
bind=,Print, exec, screenshot --copy
bind=$mainMod, Print, exec, screenshot --save
bind=$mainMod SHIFT, Print, exec, screenshot --swappy
bind=$mainMod, left, movefocus, l
bind=$mainMod, right, movefocus, r
bind=$mainMod, up, movefocus, u
bind=$mainMod, down, movefocus, d
bind=$mainMod, 1, workspace, 1
bind=$mainMod, 2, workspace, 2
bind=$mainMod, 3, workspace, 3
bind=$mainMod, 4, workspace, 4
bind=$mainMod, 5, workspace, 5
bind=$mainMod, 6, workspace, 6
bind=$mainMod, 7, workspace, 7
bind=$mainMod, 8, workspace, 8
bind=$mainMod, 9, workspace, 9
bind=$mainMod, 0, workspace, 10
bind=$mainMod SHIFT, 1, movetoworkspacesilent, 1
bind=$mainMod SHIFT, 2, movetoworkspacesilent, 2
bind=$mainMod SHIFT, 3, movetoworkspacesilent, 3
bind=$mainMod SHIFT, 4, movetoworkspacesilent, 4
bind=$mainMod SHIFT, 5, movetoworkspacesilent, 5
bind=$mainMod SHIFT, 6, movetoworkspacesilent, 6
bind=$mainMod SHIFT, 7, movetoworkspacesilent, 7
bind=$mainMod SHIFT, 8, movetoworkspacesilent, 8
bind=$mainMod SHIFT, 9, movetoworkspacesilent, 9
bind=$mainMod SHIFT, 0, movetoworkspacesilent, 10
bind=$mainMod CTRL, c, movetoworkspace, empty
bind=$mainMod SHIFT, left, movewindow, l
bind=$mainMod SHIFT, right, movewindow, r
bind=$mainMod SHIFT, up, movewindow, u
bind=$mainMod SHIFT, down, movewindow, d
bind=$mainMod CTRL, left, resizeactive, -80 0
bind=$mainMod CTRL, right, resizeactive, 80 0
bind=$mainMod CTRL, up, resizeactive, 0 -80
bind=$mainMod CTRL, down, resizeactive, 0 80
bind=$mainMod ALT, left, moveactive,  -80 0
bind=$mainMod ALT, right, moveactive, 80 0
bind=$mainMod ALT, up, moveactive, 0 -80
bind=$mainMod ALT, down, moveactive, 0 80
bind=,XF86AudioPlay,exec, playerctl play-pause
bind=,XF86AudioNext,exec, playerctl next
bind=,XF86AudioPrev,exec, playerctl previous
bind=,XF86AudioStop,exec, playerctl stop
bind=$mainMod, mouse_down, workspace, e-1
bind=$mainMod, mouse_up, workspace, e+1
bind=$mainMod, V, exec, cliphist list | rofi -dmenu -theme-str 'window {width: 50%;}' | cliphist decode | wl-copy
bind=,XF86AudioMute, exec, swayosd-client --output-volume mute-toggle
bindl=,XF86MonBrightnessUp, exec, swayosd-client --brightness raise 5%+
bindl=,XF86MonBrightnessDown, exec, swayosd-client --brightness lower 5%-
bindl=$mainMod, XF86MonBrightnessUp, exec, brightnessctl set 100%
bindl=$mainMod, XF86MonBrightnessDown, exec, brightnessctl set 0%
bindle=,XF86AudioRaiseVolume, exec, swayosd-client --output-volume +2 --max-volume=100
bindle=,XF86AudioLowerVolume, exec, swayosd-client --output-volume -2
bindle=$mainMod, f11, exec, swayosd-client --output-volume +2 --max-volume=100
bindle=$mainMod, f12, exec, swayosd-client --output-volume -2
bindm=$mainMod, mouse:272, movewindow
bindm=$mainMod, mouse:273, resizewindow
bindr=CAPS,Caps_Lock,exec,swayosd-client --caps-lock
bindr=,Scroll_Lock,exec,swayosd-client --scroll-lock
bindr=,Num_Lock,exec,swayosd-client --num-lock

exec-once = /nix/store/4a86f7kq7757fjwf5zzwk0jxixn4330n-dbus-1.14.10/bin/dbus-update-activation-environment --systemd DISPLAY HYPRLAND_INSTANCE_SIGNATURE WAYLAND_DISPLAY XDG_CURRENT_DESKTOP && systemctl --user stop hyprland-session.target && systemctl --user start hyprland-session.target
exec-once=systemctl --user import-environment &
exec-once=hash dbus-update-activation-environment 2>/dev/null &
exec-once=dbus-update-activation-environment --systemd WAYLAND_DISPLAY XDG_CURRENT_DESKTOP &
exec-once=nm-applet &
exec-once=poweralertd &
exec-once=wl-clip-persist --clipboard both &
exec-once=wl-paste --watch cliphist store &
exec-once=waybar &
exec-once=swaync &
exec-once=hyprctl setcursor Bibata-Modern-Ice 24 &
exec-once=swaybg -m fill -i $(find ~/Pictures/wallpapers/ -maxdepth 1 -type f) &
exec-once=hyprlock
exec-once=swayosd-server

windowrule=float,Viewnior
windowrule=center,Viewnior
windowrule=size 1200 800,Viewnior
windowrule=float,imv
windowrule=center,imv
windowrule=size 1200 725,imv
windowrule=float,mpv
windowrule=center,mpv
windowrule=tile,Aseprite
windowrule=size 1200 725,mpv
windowrule=float,title:^(float_kitty)$
windowrule=center,title:^(float_kitty)$
windowrule=size 950 600,title:^(float_kitty)$
windowrule=float,audacious
windowrule=pin,rofi
windowrule=tile, neovide
windowrule=idleinhibit focus,mpv
windowrule=float,udiskie
windowrule=float,title:^(Transmission)$
windowrule=float,title:^(Volume Control)$
windowrule=float,title:^(Firefox — Sharing Indicator)$
windowrule=move 0 0,title:^(Firefox — Sharing Indicator)$
windowrule=size 700 450,title:^(Volume Control)$
windowrule=move 40 55%,title:^(Volume Control)$

windowrulev2=float, title:^(Picture-in-Picture)$
windowrulev2=opacity 1.0 override 1.0 override, title:^(Picture-in-Picture)$
windowrulev2=pin, title:^(Picture-in-Picture)$
windowrulev2=opacity 1.0 override 1.0 override, title:^(.*imv.*)$
windowrulev2=opacity 1.0 override 1.0 override, title:^(.*mpv.*)$
windowrulev2=opacity 1.0 override 1.0 override, class:(Aseprite)
windowrulev2=opacity 1.0 override 1.0 override, class:(Unity)
windowrulev2=opacity 1.0 override 1.0 override, class:(floorp)
windowrulev2=opacity 1.0 override 1.0 override, class:(evince)
windowrulev2=workspace 1, class:^(floorp)$
windowrulev2=workspace 3, class:^(evince)$
windowrulev2=workspace 4, class:^(Gimp-2.10)$
windowrulev2=workspace 4, class:^(Aseprite)$
windowrulev2=workspace 5, class:^(Audacious)$
windowrulev2=workspace 5, class:^(Spotify)$
windowrulev2=workspace 8, class:^(com.obsproject.Studio)$
windowrulev2=workspace 10, class:^(discord)$
windowrulev2=workspace 10, class:^(WebCord)$
windowrulev2=idleinhibit focus, class:^(mpv)$
windowrulev2=idleinhibit fullscreen, class:^(firefox)$
windowrulev2=float,class:^(zenity)$
windowrulev2=center,class:^(zenity)$
windowrulev2=size 850 500,class:^(zenity)$
windowrulev2=float,class:^(org.gnome.FileRoller)$
windowrulev2=center,class:^(org.gnome.FileRoller)$
windowrulev2=size 850 500,class:^(org.gnome.FileRoller)$
windowrulev2=size 850 500,title:^(File Upload)$
windowrulev2=float,class:^(pavucontrol)$
windowrulev2=float,class:^(SoundWireServer)$
windowrulev2=float,class:^(.sameboy-wrapped)$
windowrulev2=float,class:^(file_progress)$
windowrulev2=float,class:^(confirm)$
windowrulev2=float,class:^(dialog)$
windowrulev2=float,class:^(download)$
windowrulev2=float,class:^(notification)$
windowrulev2=float,class:^(error)$
windowrulev2=float,class:^(confirmreset)$
windowrulev2=float,title:^(Open File)$
windowrulev2=float,title:^(File Upload)$
windowrulev2=float,title:^(branchdialog)$
windowrulev2=float,title:^(Confirm to replace files)$
windowrulev2=float,title:^(File Operation Progress)$
windowrulev2=opacity 0.0 override,class:^(xwaylandvideobridge)$
windowrulev2=noanim,class:^(xwaylandvideobridge)$
windowrulev2=noinitialfocus,class:^(xwaylandvideobridge)$
windowrulev2=maxsize 1 1,class:^(xwaylandvideobridge)$
windowrulev2=noblur,class:^(xwaylandvideobridge)$

xwayland {
  force_zero_scaling = true
}  

[kovidgoyal]

I doubt this has anything to do with kitty, probably part of the window creation/placement animation that you have configured hyprland to do. I cant replicate it on my system in hyprland.

Running kitty with

kitty -o background_opacity=0.5 -o background=red

I have limited amounts of time I can devote to window manager specific issues. But if you wish to investigate and submit a PR, feel free. Relevant code is in wl_window.c. kitty actually uses a single pixel custom surface as the background until the window is created and this reflects the background color and opacity correctly as far as I know, see attach_temp_buffer_during_window_creation().

[Frost-Phoenix]

Sorry to bother you again.
I tested with kitty -o background_opacity=0.1 -o background=red while having hyprland animations disabled and I still have the same problem.

Untitled.mp4

Do you think this could be a hyprland problem ?

[Frost-Phoenix]

I tried with an other terminal (Wezterm) and the problem didn't occurred, even with the hyprland animation enabled. So I think this might be on kitty's side and not hyprland.

[kovidgoyal]

I cannot replicate so I cant help and it definitely looks like a hyprland issue. kitty never changes the opacity of the surfaces it creates. As I said a PR is welcome.