Crash on “hb_font_get_glyph_extents” when closing Font Asset Creator window

Steps to reproduce:
1. Create new Unity project
2. Open the Font Asset Creator window (Window > Text > Font Asset Creator)
3. Close Font Asset Creator window
4. Observe the Editor

Actual results: Editor crash when Font Asset Creator window is closed
Expected results: Editor doesn’t crash when Font Asset Creator window is closed

Reproducible with versions: 6000.5.0a3 (d715b48dcd52), 6000.5.0a6
Not reproducible with versions: 6000.5.0a1, 6000.5.0a2 (4eb3f165a11f)

Tested on (OS): Ubuntu 24.04, macOS Silicon Tahoe 26.2 (M1)