[BUG] Ghostty platform-dependent font-size default not detected correctly

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Description

Summary

Fastfetch does not correctly detect Ghostty’s default font-size when those values are omitted from Ghostty’s config (i.e. when relying on Ghostty’s platform defaults, or another font matching default font-size). This results in incorrect reporting of the terminal font size on non‑macOS platforms. Verified with Ghostty version 1.2.

What’s Happening

Ghostty omits default-valued settings from ghostty +show-config.
Fastfetch’s detectGhostty():

• Parses only the printed lines.
• If font-size is missing, it unconditionally sets it to "13".
• This also applies to any configured font matching ghostty's default font-size (12 on non-macos).

However, per Ghostty’s source:

• Default font size:

  @"font-size": f32 = switch (builtin.os.tag) { .macos => 13, else => 12, }

  Meaning: macOS = 13, all other platforms = 12.

Reproduction Steps

1. Use Ghostty 1.2 on (for example) Linux.
2. Ensure font-size is omitted or explicitly set to 12.
3. Run:

   ghostty +show-config | grep '^font-size'

   (No output—because default.)
4. Run:

   fastfetch -s terminalfont

   Observed: reports font-size 13.
   Expected: font-size 12.
5. Set font-size = 14 in Ghostty config.
6. Run both commands again:
   • ghostty +show-config now prints font-size = 14
   • Fastfetch reports 14 correctly.

Actual vs Expected

Platform	Config (font-size)	Ghostty prints line?	Fastfetch (current)	Expected
Linux	omitted / 12	no	13	12
Linux	14	yes	14	14
macOS	omitted / 13	no	13	13
macOS	12	yes	12	12

Root Cause

• Ghostty suppresses default-valued keys → fastfetch sees no font-size line.
• Fastfetch assumes absence means “use 13.”
• Ghostty’s default differs by platform (13 only on macOS).

Version used

fastfetch 2.53.0 (x86_64)

Bug prevalence

Always

Regression

Not sure

Installation

Package manager

Package manager

pacman

Screenshots

No response

Configuration

System information

N/A

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