You'll notice
A new hidden character, U+16FE4, is now blocked as a potential steganography risk
What
Claude Code's checks for invisible or hidden characters now also flag codepoint 94180 (U+16FE4), alongside characters it already blocked such as the zero-width no-break space (65279) and the tag character range (917504-917999).
Why
This closes another way invisible characters could be smuggled into text, since such characters can be used to hide instructions or content that isn't visibly displayed.