[jxiwang]

Summary

Add amp-semantic/visibility to the established capture runtime and Session Replay integration. The recorder emits deduplicated hidden/visible transitions, includes runtime-provided version and identity, and removes its listener on stop. Focus/blur alone do not emit events; context already supplies the initial visibility state.

Include the visibility payload/schema, default registration and budget, listener cleanup tests, playground description, and Chromium tests of visibility delivery and timestamp ordering. Native tab scheduling remains browser-dependent; browser tests use deterministic visibility notifications.

Capture uses the locally supplied semanticCapture.createCapture: createSemanticCapture callback introduced in #2127. The base Session Replay SDK has no production dependency on amp-semantic. Adding visibility leaves the base Session Replay bundle at 142.78 kB gzip within its limit.

Stack

Base: #2127 (codex/semantic-replay-integration). Merge runtime, context, and Session Replay integration first, then retarget this PR to main.

Validation

Node 24: install, full workspace build, docs, lint, dependency checks, typecheck, and tests across all 32 workspace projects passed. Seven Chromium transport tests and existing bundle-size limits passed. Session Replay is 142.78 kB gzip and unified is about 231 kB gzip; source maps contain no amp-semantic modules. Semantic and affected Session Replay packages retain 100% coverage.

Existing blocker retained with prior maintainer approval: pnpm test:examples cannot start because jest.setup.examples.js is absent on main.

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Note

Low Risk
Additive recorder and schema behind existing opt-in semantic capture; changes are covered by unit, schema, and Playwright tests with no auth or sensitive data handling changes.

Overview
Adds a visibility semantic event family alongside context, wired through createSemanticCapture defaults, schema, and Session Replay transport.

The new visibilityRecorder listens for deduplicated document.visibilitychange transitions (hidden / visible), ignores focus/blur-only signals, tears down on stop, and emits runtime-stamped amp-semantic/visibility custom events with the same per-session budget as context. defaultRecorders, SEMANTIC_CAPS, and payload types now include visibility; schema.json validates the new tag and tracks visibility in caps_hit.

Playwright replay tests, unit tests, the local semantic harness, README, and joined-config coverage are updated so both families can be gated remotely/locally and visibility shows up in end-to-end delivery checks.

^{Reviewed by Cursor Bugbot for commit 823c6a8. Bugbot is set up for automated code reviews on this repo. Configure here.}

[github-actions]

size-limit report 📦

Path	Size
packages/analytics-browser/lib/scripts/amplitude-min.js.gz	68.41 KB (0%)
packages/session-replay-browser/lib/scripts/session-replay-browser-min.js.gz	140.38 KB (0%)
packages/unified/lib/scripts/amplitude-min.umd.js.gz	226.82 KB (0%)
@amplitude/element-selector (gzipped esm)	3.48 KB (0%)
@amplitude/analytics-browser/lite (gzipped CDN bundle)	21.34 KB (0%)

[github-actions]

Session Replay Browser E2E Results

 158 passed
 1 flaky

Details

 159 tests across 18 suites
 4 minutes, 10 seconds
 823c6a8

Flaky tests

chromium › e2e/shadow-dom.spec.ts › captureAdoptedStyleSheets option › SDK initializes without error and captures shadow host with default (true)

[jxiwang]

bugbot run

[cursor]

✅ Bugbot reviewed your changes and found no new issues!

Comment @cursor review or bugbot run to trigger another review on this PR

^{Reviewed by Cursor Bugbot for commit 5b99f6f. Configure here.}

[linear-code]

SRAI-129