feat: session recording tracks previous and next session id #2503

pauldambra · 2025-10-25T16:31:33Z

when watching a session it might end because a user went idle, but to the user they're just picking up after a long gap

let's track previous and next session, so we can let watchers navigate backwards and forwards in the UI

we could look up this data but it's relatively slow to query and we can just store it in the SDK instead

Release info Sub-libraries affected

Libraries affected

Checklist

Tests for new code
Accounted for the impact of any changes across different platforms
Accounted for backwards compatibility of any changes (no breaking changes!)
Took care not to unnecessarily increase the bundle size

If releasing new changes

Ran pnpm changeset to generate a changeset file
Added the "release" label to the PR to indicate we're publishing new versions for the affected packages

vercel · 2025-10-25T16:31:35Z

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pauldambra · 2025-10-25T16:31:55Z

feat: session recording tracks previous and next session id #2503 : 2 dependent PRs (#2524 , #2525 ) 👈 (View in Graphite)
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github-actions · 2025-10-25T16:35:21Z

Download bundle size visualization

github-actions · 2025-10-25T16:38:34Z

Size Change: +490 B (+0.01%)

Total Size: 4.87 MB

Filename	Size	Change
`packages/browser/dist/lazy-recorder.js`	147 kB	+245 B (+0.17%)
`packages/browser/dist/posthog-recorder.js`	242 kB	+245 B (+0.1%)

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_{compressed-size-action}

pauldambra · 2025-10-29T14:02:48Z

packages/browser/src/extensions/replay/external/lazy-loaded-session-recorder.ts

    private _onSessionIdCallback: SessionIdChangedCallback = (sessionId, windowId, changeReason) => {
-        if (changeReason) {
-            this._tryAddCustomEvent('$session_id_change', { sessionId, windowId, changeReason })
+        if (!changeReason) return


as a follow-up here... i know why we'd ignore part of this for no change reason.
but maybe we shouldn't ignore all of it 🤔

pauldambra force-pushed the feat/track-prev-next branch from 73067fb to e7b03ee Compare October 25, 2025 16:33

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pauldambra force-pushed the feat/track-prev-next branch from e7b03ee to 00a0fbd Compare October 28, 2025 22:28

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pauldambra force-pushed the feat/track-prev-next branch from cafdfbd to fa2e313 Compare October 29, 2025 11:58

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pauldambra force-pushed the feat/track-prev-next branch from fa2e313 to edc24cb Compare October 29, 2025 13:58

pauldambra commented Oct 29, 2025

View reviewed changes

pauldambra force-pushed the feat/track-prev-next branch from edc24cb to 705452e Compare October 29, 2025 14:05

pauldambra requested review from a team, TueHaulund, ksvat and veryayskiy and removed request for a team October 29, 2025 14:05

pauldambra added the release label Oct 29, 2025 — with Graphite App

pauldambra force-pushed the feat/track-prev-next branch from 705452e to ab2c819 Compare October 29, 2025 14:08

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pauldambra added 2 commits October 29, 2025 18:54

feat: session recording tracks previous and next session id

f628ba6

retry more on flake

dd6b0ab

pauldambra force-pushed the feat/track-prev-next branch from ab2c819 to dd6b0ab Compare October 29, 2025 18:55

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This was referenced Oct 29, 2025

fix: code golf with the unminifiable strings in constants #2524

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