Invisible characters can explain visible bugs

An invisible-character detector reveals characters such as nonbreaking spaces, zero-width joiners, and control marks that ordinary editors may hide. These can explain why two strings look identical but fail a comparison, why a URL breaks, or why text wraps unexpectedly.

Paste a short known sample and inspect code points or positions, not just a highlighted preview. Do not delete every invisible character automatically: some are meaningful in scripts, emoji sequences, or bidirectional text. Compare the original and cleaned strings byte-for-byte when identifiers or code are involved. For user-facing prose, inspect whether replacing a nonbreaking space changes layout before saving.