upgrading from v0.40 to v0.41 breaks color emoji

[nathanlisabio]

Describe the bug
color emoji rendering not rendering properly

To Reproduce
Steps to reproduce the behavior:
the specific scenario where i noticed this behaviour:

1. granted aws assume tool, run assume {profile} -t, while also using starship prompt

Screenshots
v0.40.x

 kitty --debug-font-fallback                                                                                                                                   
                                                                                
[0.254] Text fonts:
[0.254]   Normal: DejaVuSansMono: /usr/share/fonts/truetype/dejavu/DejaVuSansMono.ttf:0
Features: ()
[0.254]   Bold: DejaVuSansMono-Bold: /usr/share/fonts/truetype/dejavu/DejaVuSansMono-Bold.ttf:0
Features: ()                                                                                                                                                    
[0.254]   Italic: DejaVuSansMono-Oblique: /usr/share/fonts/truetype/dejavu/DejaVuSansMono-Oblique.ttf:0
Features: ()                                                                                                                                                    
[0.254]   Bold-Italic: DejaVuSansMono-BoldOblique: /usr/share/fonts/truetype/dejavu/DejaVuSansMono-BoldOblique.ttf:0
Features: ()                                                                                                                                                    
[0.410] U+2601 U+fe0f bold emoji_presentation Face(family=Noto Color Emoji style=Regular ps_name=NotoColorEmoji path=/usr/share/fonts/truetype/noto/NotoColorEmoji.ttf ttc_index=0 variant=False named_instance=False
 scalable=False color=True)                                                                                                                                     
^C⏎

v0.41.0

zsh ➜ kitty --debug-font-fallback
[0.097] Text fonts:
[0.097]   Normal: DejaVuSansMono: /usr/share/fonts/truetype/dejavu/DejaVuSansMono.ttf:0
Features: ()
[0.097]   Bold: DejaVuSansMono-Bold: /usr/share/fonts/truetype/dejavu/DejaVuSansMono-Bold.ttf:0
Features: ()
[0.097]   Italic: DejaVuSansMono-Oblique: /usr/share/fonts/truetype/dejavu/DejaVuSansMono-Oblique.ttf:0
Features: ()
[0.097]   Bold-Italic: DejaVuSansMono-BoldOblique: /usr/share/fonts/truetype/dejavu/DejaVuSansMono-BoldOblique.ttf:0
Features: ()
[0.149] U+1f182 bold Face(family=Noto Sans Symbols style=Bold ps_name=NotoSansSymbols-Bold path=/usr/share/fonts/truetype/noto/NotoSansSymbols-Bold.ttf ttc_index=0 variant=False named_instance=False scalable=True color=False)
^C%                                  

Environment details

kitty 0.41.0 (26747284bb) created by Kovid Goyal
Linux ubuntu9950x 6.11.0-21-generic #21~24.04.1-Ubuntu SMP PREEMPT_DYNAMIC Mon Feb 24 16:52:15 UTC 2 x86_64
Ubuntu 24.04.2 LTS ubuntu9950x /dev/tty

DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=24.04
DISTRIB_CODENAME=noble
DISTRIB_DESCRIPTION="Ubuntu 24.04.2 LTS"
Running under: Wayland (GNOME Shell 46.0) missing: blur server_side_decorations cursor_shape layer_shell icon
OpenGL: '4.6 (Core Profile) Mesa 24.2.8-1ubuntu1~24.04.1' Detected version: 4.6
Frozen: True
Fonts:
  medium: DejaVuSansMono: /usr/share/fonts/truetype/dejavu/DejaVuSansMono.ttf:0
          Features: ()
    bold: DejaVuSansMono-Bold: /usr/share/fonts/truetype/dejavu/DejaVuSansMono-Bold.ttf:0
          Features: ()
  italic: DejaVuSansMono-Oblique: /usr/share/fonts/truetype/dejavu/DejaVuSansMono-Oblique.ttf:0
          Features: ()
      bi: DejaVuSansMono-BoldOblique: /usr/share/fonts/truetype/dejavu/DejaVuSansMono-BoldOblique.ttf:0
          Features: ()
Paths:
  kitty: /home/nathan/.local/kitty.app/bin/kitty
  base dir: /home/nathan/.local/kitty.app/lib/kitty
  extensions dir: /home/nathan/.local/kitty.app/lib/kitty-extensions
  system shell: /usr/bin/zsh
System color scheme: dark. Applied color theme type: none

Config options different from defaults:

Important environment variables seen by the kitty process:
	PATH                                /home/nathan/.local/kitty.app/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin:/snap/bin
	LANG                                en_US.UTF-8
	SHELL                               /usr/bin/zsh
	DISPLAY                             :0
	WAYLAND_DISPLAY                     wayland-0
	USER                                nathan
	XDG_RUNTIME_DIR                     /run/user/1000
	XDG_DATA_DIRS                       /usr/local/share/:/usr/share/:/var/lib/snapd/desktop
	XDG_CURRENT_DESKTOP                 ubuntu:GNOME
	XDG_MENU_PREFIX                     gnome-
	XDG_SESSION_CLASS                   user
	XDG_SESSION_DESKTOP                 ubuntu
	XDG_SESSION_TYPE                    wayland

Additional context
I noticed the difference was the NotoSansSymbols vs NotoColorEmoji. But on apt list --installed | grep noto, i see that the fonts installed are the same (i'm comparing it from a computer that has updated to v0.41 vs one that was still on v.0.40)

ubuntu 24.04

[nathanlisabio]

refs that i tried to follow to resolve:
#73

[kovidgoyal]

Looking at your debug output, in one case the symbol is
U+2601 U+fe0f and in the other its U+1f182

Your issue is happening because of that. Basically in the second case U+1f182 is being found in Noto Sans Symbol, then when its time to render U+2601 it is found in the already loaded Noto Sans Symbol which cant actually render it because of the following u+fe0f. This doesnt have anything to do with 40 vs 41 there were anyway no changes to font selection between them.

Either uninstall noto sans symbol or use symbol_map in kitty.conf to force kitty to use noto color emoji for u+2601

[kovidgoyal]

Actually, thinking about it there may have been one change in 0.41 that could affect this, I will take another look when I have a moment.

[ronjouch]

I confirm the issue, and fix in 0.41.1. Thx @nathanlisabio for the report, thx Kovid for the quick fix.

[kovidgoyal]

You are welcome!