Conjecture 143 was unsettled since 1988 — no attribution, no date, no disposition in Graffiti source

Unlike WOW 136 which had a known origin, conjecture 143 appears in the Graffiti source at line 1838 with no attribution, date, or disposition — meaning it had no known pedigree and no prior attempted resolution. Opus 5 identified it as a stale open problem from approximately 1988. The kite witness K(21,22) provides the first known counterexample after ~38 years.