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A subscriber that arrives mid-stream cannot start from `render()`. Damage describes what changed since someone last looked, so a newcomer is handed whatever happens next -- on a quiet terminal, the cursor's line alone -- painted onto a blank screen. Upstream's `mark_fully_damaged` is private, so an embedder cannot ask for a full frame that way either. `snapshot()` copies the whole visible viewport instead, marks the frame full so a reused encoder's dedup hashes realign, and stamps the geometry it was captured under. The delicate part is what it does not do. Damage is a single shared cursor across every subscriber, so a snapshot that consumed it would steal the incumbent renderer's pending rows: the newcomer's full frame would look perfect while the established renderer silently froze. `capture_all` therefore never calls `damage()` or `reset_damage()`, and their absence is the mechanism. Proving that needed more care than the interleaving alone. Because `Term::damage()` marks the cursor line on every call, an incumbent owed only the row it sits on gets that row back even when its damage was stolen -- so the first version of the fixture passed against a deliberately naive implementation. The committed fixture rewrites row 0 and parks the cursor on row 3, putting the owed row where the cursor cannot return it for free; it fails when snapshot consumes damage, and again when snapshot copies damaged rows only or omits the full flag. Co-authored-by: tlongwell-block <109685178+tlongwell-block@users.noreply.github.com> Signed-off-by: tlongwell-block <109685178+tlongwell-block@users.noreply.github.com>