Comment by doodpants

You and me both. Ligatures are a solution to a problem that monospaced fonts don't have. I don't mind if a mono font uses ligatures to harmonize character spacing/alignment a little bit. But I don't want things like a "proper" greater/less-equal sign; if a font goes so far as to replace >= with ≥, then it's lying to me about what characters are actually present in the file.