Ghostty crashes when the system has a font with null display name

[BasixKOR]

Issue Description

Before all, for transparency: All of the diagnosing work was done by Fable 5 on Claude Code. I'm writing this based on what Fable reported to me.

So I have been having a pretty weird issue. When I use Claude Code, at some point in time Ghostty crashes. The exact trigger was very unclear and sometimes I was able to get an answer from it but I wasn't able to use it more than a few turns.

I figured I could ask Fable to debug this and it found that when a font with no display name is installed on system, Ghostty fails when it tries to list out the system fonts. Fable pointed this down to font.DeferredFace.name being null. Turns out my font manager had some fonts installed to my Mac, which had a invalid name field.

Crash details

exception: EXC_BAD_ACCESS (code 0x1), fault address = 0x0
crashing thread pc: CoreFoundation + 0x15078c   (CFSt*/cstring path)
                lr: CoreFoundation + 0x7620
frame #2:          ghostty + 0x4f0ed4          == font.DeferredFace.name + 324

Expected Behavior

ghostty +list-fonts should not crash when a font with a display name set to null.

Actual Behavior

It crashes.

Reproduction Steps

1. Have a font with no display name set. This is kinda hard as the fonts available online is mostly valid ones, and I used a script to reproduce it reliably.
2. Run ghostty +list-fonts
3. It crashes.

Ghostty Logs

Timestamp                       Thread     Type        Activity             PID    TTL
2026-07-10 02:43:55.448249+0900 0x25f9f6   Info        0x0                  79234  0    ghostty: [com.mitchellh.ghostty:default] ghostty version=1.3.2-main-+b14d92383
2026-07-10 02:43:55.448775+0900 0x25f9f6   Info        0x0                  79234  0    ghostty: [com.mitchellh.ghostty:default] ghostty build optimize=ReleaseFast
2026-07-10 02:43:55.448783+0900 0x25f9f6   Info        0x0                  79234  0    ghostty: [com.mitchellh.ghostty:default] runtime=.none
2026-07-10 02:43:55.448787+0900 0x25f9f6   Info        0x0                  79234  0    ghostty: [com.mitchellh.ghostty:default] font_backend=.coretext
2026-07-10 02:43:55.448790+0900 0x25f9f6   Info        0x0                  79234  0    ghostty: [com.mitchellh.ghostty:default] renderer=renderer.generic.Renderer(renderer.Metal)
2026-07-10 02:43:55.448793+0900 0x25f9f6   Info        0x0                  79234  0    ghostty: [com.mitchellh.ghostty:default] libxev default backend=kqueue
2026-07-10 02:43:55.450155+0900 0x25f9f6   Info        0x0                  79234  0    ghostty: [com.mitchellh.ghostty:os_locale] os_locale: setlocale from env result=en_US.UTF-8
2026-07-10 02:43:55.454476+0900 0x25f9f6   Info        0x0                  79234  0    ghostty: [com.mitchellh.ghostty:default] executing CLI action=.list-fonts
2026-07-10 02:43:55.455561+0900 0x25f9f7   Info        0x0                  79234  0    ghostty: [com.mitchellh.ghostty:sentry] sentry: sentry envelope does not contain crash, discarding
2026-07-10 02:44:06.476390+0900 0x25fbae   Info        0x0                  79288  0    ghostty: [com.mitchellh.ghostty:default] ghostty version=1.3.2-main-+b14d92383
2026-07-10 02:44:06.476539+0900 0x25fbae   Info        0x0                  79288  0    ghostty: [com.mitchellh.ghostty:default] ghostty build optimize=ReleaseFast
2026-07-10 02:44:06.476546+0900 0x25fbae   Info        0x0                  79288  0    ghostty: [com.mitchellh.ghostty:default] runtime=.none
2026-07-10 02:44:06.476551+0900 0x25fbae   Info        0x0                  79288  0    ghostty: [com.mitchellh.ghostty:default] font_backend=.coretext
2026-07-10 02:44:06.476554+0900 0x25fbae   Info        0x0                  79288  0    ghostty: [com.mitchellh.ghostty:default] renderer=renderer.generic.Renderer(renderer.Metal)
2026-07-10 02:44:06.476557+0900 0x25fbae   Info        0x0                  79288  0    ghostty: [com.mitchellh.ghostty:default] libxev default backend=kqueue
2026-07-10 02:44:06.476825+0900 0x25fbae   Info        0x0                  79288  0    ghostty: [com.mitchellh.ghostty:os_locale] os_locale: setlocale from env result=en_US.UTF-8
2026-07-10 02:44:06.476902+0900 0x25fbae   Info        0x0                  79288  0    ghostty: [com.mitchellh.ghostty:default] executing CLI action=.list-fonts
2026-07-10 02:44:06.479299+0900 0x25fbaf   Error       0x0                  79288  0    ghostty: [com.mitchellh.ghostty:sentry] sentry: crash report written to disk path=/Users/basix/.local/state/ghostty/crash/ce014ef2-2220-4e0d-9550-568ebb5a8b29.ghosttycrash

Ghostty Version

Ghostty 1.3.2-main-+b14d92383 (channel: tip)
Zig 0.15.2, ReleaseFast, font engine: coretext, renderer: Metal
macOS 26.5.1 (25F80), Apple Silicon

OS Version Information

macOS 26.5.1 (25F80)

(Linux only) Display Server

None

(Linux only) Desktop Environment/Window Manager

No response

Minimal Ghostty Configuration

# Setting a font with less symbols is likely to cause crashes due to Ghostty's fallback behaviour.
# The following is my Ghostty config.

theme = Catppuccin Mocha

font-family = "NeoDunggeunmo Code"
font-size = 16

macos-titlebar-style = tabs
background-opacity = 0.85
background-blur-radius = 20

mouse-hide-while-typing = true

copy-on-select = true
clipboard-trim-trailing-spaces = true
shell-integration-features = ssh-terminfo,ssh-env

# Ghostty has a weird name for backtick.
keybind = global:cmd+grave_accent=toggle_quick_terminal

# Local
config-file = "config-local"
keybind = shift+enter=text:\x1b\r # Claude keeps adding this?

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.