Exact text bytes, no silent character expansion
Input is NFC-normalized for composed characters such as é, but one unsupported character is never silently expanded into multiple supported letters. Copy/download and unsupported-character review are built in.
International Morse boundary
WebToolArc follows ITU-R M.1677-1 for the International Morse alphabet and the 1-dot / 3-dot / 7-dot spacing relationships. Common extensions are labeled separately, and learning-oriented Farnsworth spacing changes gaps without changing dit/dah character speed.