Release-cycle red-team found two same-id footnoteDefinition nodes (trivially
produced by markdown import [^d]: first / [^d]: second, or paste/duplicate)
caused silent data loss: scan() used a last-wins Map and the sync rebuild
(addToHistory:false, propagated via Yjs, un-undoable) dropped all but the last.
Fix resolves collisions so BOTH survive, with a DETERMINISTIC id scheme so
collaborators converge:
- deriveFootnoteId(originalId, occurrence, taken): the k-th (k>=2) occurrence of
id X becomes X__k, bumped with a deterministic alpha suffix only against the
doc's own id set — a pure function of document state. No Math.random/Date.now
on the sync or import paths (random uuid stays only in setFootnote, where a
single user originates a brand-new id).
- footnote-sync.resolveCollisions walks refs+defs in document order, re-ids
duplicate references via setNodeMarkup and pairs them 1:1 with definitions;
single SYNC_META-tagged transaction, returns null when canonical (terminates).
- Markdown import (footnote.marked) + MCP mirror (collaboration.ts) dedup with
the same deterministic scheme + marker rewrite; packages/mcp/build regenerated.
- Paste plugin remaps colliding pasted ids against the current doc.
Tests: two independent editors resolving the same duplicate-id doc produce
IDENTICAL ids (the cross-client determinism guard that the random version would
fail); both definitions survive the first edit; import dedup is deterministic.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>