CLAUDE WATERMARK REMOVER · DESTINATION TEST
Can Buffer.fill repeat an emoji safely into an arbitrary byte width?
The measured five-byte fill repeats the emoji bytes partially, and decoding adds a replacement character.
What the test establishes
The cleaned emoji encodes to four bytes. Filling five bytes repeats the first byte of the next copy without the remaining continuation bytes. UTF-8 decoding therefore yields the original emoji followed by a replacement character. For repeated text, construct complete text repetitions before encoding and validate the byte budget rather than using byte-pattern fill as a text layout operation.
Reproduce the observation
Save tested-app.js and reproduce.cjs together, then run node reproduce.cjs. Compare its output with the recorded observation. The harness executes the actual homepage callback in a minimal DOM and records its resulting field values and method calls. Destination operations run in Node.js; the homepage DOM is a controlled substitute. Runtime: v24.22.1. No submitted text or genuine Claude output is used.
{
"cleaned": "😀",
"hex": "f09f9880f0",
"decoded": "😀�"
}Capability boundary
This measures Node Buffer.fill and default UTF-8 decoding. It does not imply the cleaner introduces U+FFFD, and differs from slicing a previously encoded byte prefix.
This Claude watermark remover edits a small selected character set. These callback observations do not establish authorship, detector scores, statistical-watermark removal or end-to-end browser behavior. For real work, keep the original and compare the exact result at its destination.
Primary material and next step
The tested first-party source snapshot and complete harness are the primary material for this page. For broader scope, read invisible Unicode versus AI watermarks, or return to the cleaner.