Try converting the patched file to a different format (e.g., .ttf to .woff) using online converters, which sometimes bypasses minor header corruption.
E-ink screens have slow refresh rates. Vector fonts can ghost badly. A patched, high-contrast bitmap font like font60 refreshes instantly. Users on MobileRead forums have reported using the patched version to fix missing Japanese or Korean characters on their hacked Kobos.
Your terminal emulator does not support Unicode beyond the BMP (Basic Multilingual Plane). Switch to Alacritty, Kitty, or WezTerm. The default macOS Terminal.app is notoriously bad at this.
If you saw "jcheada font60 patched" in a terminal, error log, or download:
Many patched versions include programming ligatures, turning -> into a sleek arrow or != into a single, crossed-out equals sign. How to Install JCheada Font60 Patched