Font configuration ignored when using Japanese locale

[Ryuuusuke]

Issue Description

I installed ghostty from ghostty-ubuntu repository and ghostty always ignored my font configuration and set the font to Takao. It's because I have Japanese Locale and language, after I tried to change it to en_us, it work's fine

Expected Behavior

• Primary font from config should be used for Latin characters (e.g., Iosevka)
• Noto Sans Mono CJK JP as fallback font
• Japanese glyphs should only use fallback font

Actual Behavior

• Takao font becomes the default for all glyphs
• Font Config is ignored silently

Reproduction Steps

1. Install ghostty from ghotty-ubuntu repo
2. Set system locale and language to Japanese
3. Install Takao font

Ghostty Logs

% ghostty
info: ghostty version=1.2.3
info: ghostty build optimize=ReleaseFast
info: runtime=apprt.Runtime.gtk
info: font_backend=font.main.Backend.fontconfig_freetype
info: dependency harfbuzz=8.3.0
info: dependency fontconfig=21500
info: renderer=renderer.generic.Renderer(renderer.OpenGL)
info: libxev default backend=io_uring
info(os_locale): setlocale from env result=ja_JP.UTF-8
info(gtk): GTK version build=4.14.5 runtime=4.14.5
info(gtk): libadwaita version build=1.5.0 runtime=1.5.0
info: reading configuration file path=/home/ryusuke/.config/ghostty/config
info(config): default shell source=env value=/bin/zsh
warning(gtk_ghostty_application): setting GDK_DEBUG=gl-disable-gles,gl-no-fractional,vulkan-disable
warning(gtk_ghostty_application): setting GDK_DISABLE=color-mgmt

(process:5906): Gtk-WARNING **: 07:37:18.004: Theme directory scalable/emotes of theme Cosmic has no size field


(process:5906): Gtk-WARNING **: 07:37:18.004: Theme directory scalable/legacy of theme Cosmic has no size field


(process:5906): Gtk-WARNING **: 07:37:18.005: Theme directory scalable/ui of theme Cosmic has no size field


(process:5906): Gtk-WARNING **: 07:37:18.005: Theme directory scalable-up-to-32/status of theme Cosmic has no size field

info(gtk_ghostty_application): cgroup isolation disabled via config=config.Config.LinuxCgroup.single-instance

(process:5906): Gtk-WARNING **: 07:37:18.153: Theme directory scalable/emotes of theme Cosmic has no size field


(process:5906): Gtk-WARNING **: 07:37:18.154: Theme directory scalable/legacy of theme Cosmic has no size field


(process:5906): Gtk-WARNING **: 07:37:18.154: Theme directory scalable/ui of theme Cosmic has no size field


(process:5906): Gtk-WARNING **: 07:37:18.154: Theme directory scalable-up-to-32/status of theme Cosmic has no size field

info(opengl): loaded OpenGL 4.6
info(font_shared_grid_set): font regular: Takaoゴシック
info(font_shared_grid_set): font regular: Takaoゴシック
info(font_shared_grid_set): font bold: Takaoゴシック
info(font_shared_grid_set): font bold: Takaoゴシック
info(font_shared_grid_set): font italic: Takaoゴシック
info(font_shared_grid_set): font italic: Takaoゴシック
info(font_shared_grid_set): font bold_italic: Takaoゴシック
info(font_shared_grid_set): font bold_italic: Takaoゴシック
info(io_exec): found Ghostty resources dir: /usr/share/ghostty
info(io_exec): shell integration automatically injected shell=termio.shell_integration.Shell.zsh
warning(gtk_ghostty_application): unimplemented action=apprt.action.Action.Key.cell_size
info(io_exec): started subcommand path=/bin/sh pid=5938
info(io_exec): subcommand cgroup=-

Ghostty Version

Ghostty 1.2.3

Version
  - version: 1.2.3
  - channel: stable
Build Config
  - Zig version   : 0.14.1
  - build mode    : builtin.OptimizeMode.ReleaseFast
  - app runtime   : apprt.Runtime.gtk
  - font engine   : font.main.Backend.fontconfig_freetype
  - renderer      : renderer.generic.Renderer(renderer.OpenGL)
  - libxev        : io_uring
  - kernel version: 6.17.4-76061704-generic
  - desktop env   : other
  - GTK version   :
    build         : 4.14.5
    runtime       : 4.14.5
  - libadwaita    : enabled
    build         : 1.5.0
    runtime       : 1.5.0
  - libX11        : enabled
  - libwayland    : enabled

OS Version Information

Pop!_OS 24.04 LTS x86_64

(Linux only) Display Server

Wayland

(Linux only) Desktop Environment/Window Manager

COSMIC

Minimal Ghostty Configuration

# fonts
font-family = "Iosevka Extended"
font-family = "Noto Sans Mono CJK JP"
font-size = 12

# themes
theme = "Adventure"
background = #000000

# window
window-decoration = none
window-padding-x = 9
window-padding-y = 4

# etc
confirm-close-surface = false

Additional Relevant Configuration

No response

I acknowledge that:

• I have reviewed the FAQ and confirm that my issue is NOT among them.
• I have searched the Ghostty repository (both open and closed Discussions and Issues) and confirm this is not a duplicate of an existing issue or discussion.
• I have checked the "Preview" tab on all text fields to ensure that everything looks right, and have wrapped all configuration and code in code blocks with a group of three backticks (```) on separate lines.