[Eugene (OEvgeny)]

A livestream revision received again with the same ID (e.g. after a reconnect) is added to its session a second time; development builds throw "graph has N activities, Redux has N+1 activities".

Changelog Entry

Fixed

• Fixed livestream revisions re-sent with the same ID shown twice, in PR #5969, by @OEvgeny

Description

upsert() inserted a re-sent livestream revision into its session without removing its previous entry, so sortedActivities listed it twice. A known activity now skips the streaming fast path, and the slow path replaces its previous session entry.

Design

• The fast path stays insert-only: a re-sent revision is rare, so it falls back to the slow path (an O(1) activityMap check) instead of teaching the fast path to splice out the old entry.

Specific Changes

• sort/upsert.ts: skip the fast path for known activities; remove a revision's previous entry before inserting it into its session
• upsert.livestream.spec.ts, upsert.howToWithLivestream.spec.ts: a re-sent revision stays once in the session and in sortedActivities (fast and slow path)
• livestream/resentRevision.html (+ .entity): snapshot 1, one message with the third revision; the store and activity key list each revision once

• I have added tests and executed them locally
• I have added .changelog/<PR#>-<slug>.md
• I have updated documentation

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