If exact byte equality matters, hash the original and copied text with the same algorithm and compare the full digests. A mismatch means something changed, even if the text looks identical.
Before hashing, decide whether line endings, Unicode normalization, or trailing spaces should count as differences. If the digests differ, use Text Diff or a byte-aware tool to locate the change. Do not paste secrets into an untrusted online service.
Does visual similarity or exact byte equality matter here?
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