HTML Entity - Tilde

Mistake: Confusing a standalone diacritical mark with a precomposed accented letter

Fix: Standalone diacritical marks (like ¨ or ˆ) are combining characters or spacing marks. Precomposed letters (like ü or ê) are single characters. Use the precomposed form for normal text and the standalone form only when discussing the mark itself.

Mistake: Using diacritical marks with the wrong base letter

Fix: Not every diacritic combines with every letter. For example, ñ (n-tilde) is valid in Spanish, but m-tilde is not a standard character in any language.