ClassicAPI's remote-cast cache is stamped from SMSG_SPELL_START and only
expires by computed end time — 1.12 keeps no per-unit interrupt record,
so an interrupted cast kept animating on the plate until its would-be
finish (BG flag caps being the loudest repro).
Nampower does surface the missing signal in Lua: SPELL_FAILED_OTHER
(casterGuid, spellId; fired from the SMSG_SPELL_FAILED_OTHER handler)
and UNIT_DIED (guid). Stamp a guid-keyed suppression time on either
event and have GetCastInfo drop any cast that started before the stamp;
a newer cast clears its unit's entry. Both castbar paths (dedicated
target frame + central loop) already funnel through GetCastInfo, so one
check covers them. The handler only stamps when the unit actually has a
tracked cast, and flags the plate via castUpdate for a same-tick hide.
Brues
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