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+---
+phase: 23-verification
+type: uat
+status: pending
+---
+
+# Phase 23: Memory Leak Verification UAT
+
+## Prerequisites
+
+- **Browser:** Chrome (recommended for DevTools memory profiling)
+- **DevTools:** Open with Performance Monitor and Memory tabs visible
+- **jam-ui:** Running locally (`npm run start`)
+- **web backend:** Running (`./runweb`)
+- **Native client:** Running and connected
+
+## Quick Verification (5 minutes)
+
+Before full verification, confirm basic stability:
+
+1. Join a session
+2. Open/close chat window 3 times
+3. Show/hide VU meters 3 times
+4. Leave session
+5. Verify no console errors
+
+**Quick check pass:** [ ]
+
+---
+
+## Section 1: VU Meter Verification (Phase 20 fixes)
+
+**Purpose:** Verify vuStates cleanup when tracks are removed (VUMTR-02, VUMTR-03)
+
+### Test Steps
+
+1. **Open React DevTools**
+   - Press F12 > Components tab
+   - Find VuContext provider in the component tree
+
+2. **Join Session with Tracks**
+   - Join a session with at least one other participant
+   - Note the initial vuStates keys in VuContext
+
+3. **Record Initial State**
+   - Inspect VuContext state
+   - Record number of mixer IDs in vuStates: ______
+
+4. **Simulate Track Changes**
+   - If possible, have participants join/leave
+   - OR: Navigate away and back to session (triggers track refresh)
+   - Repeat 3 times
+
+5. **Verify Cleanup**
+   - Check vuStates keys in VuContext
+   - vuStates should ONLY contain active mixer IDs
+   - No orphaned entries from removed tracks
+
+### Expected Results
+
+| Check | Expected | Actual |
+|-------|----------|--------|
+| vuStates keys match active mixers | Yes | |
+| No orphaned mixer IDs | Yes | |
+| Console errors | None | |
+
+**Section 1 Pass:** [ ]
+
+---
+
+## Section 2: Chat Memory Verification (Phase 21 fixes)
+
+**Purpose:** Verify bounded message storage and cleanup on session leave (CHAT-02, CHAT-03)
+
+### Test Steps
+
+1. **Open Session and Chat Window**
+   - Join any session
+   - Click the chat button to open chat window
+
+2. **Send Messages**
+   - Send at least 10 test messages
+   - Messages should appear in chat list
+
+3. **Verify Bounded Storage**
+   - Open Redux DevTools (requires Redux DevTools extension)
+   - Navigate to state > sessionChat > messagesByChannel
+   - Note message count: ______
+   - Verify messages array length is reasonable (max 500 per channel)
+
+4. **Leave Session**
+   - Click the leave button to exit session
+   - Navigate to dashboard
+
+5. **Verify Chat Cleanup**
+   - Open Redux DevTools
+   - Check sessionChat.messagesByChannel
+   - Should be empty object `{}`
+
+### Expected Results
+
+| Check | Expected | Actual |
+|-------|----------|--------|
+| Messages bounded (< 500) | Yes | |
+| Chat cleared on leave | Yes | |
+| lastReadAt preserved | Yes | |
+| Console errors | None | |
+
+**Section 2 Pass:** [ ]
+
+---
+
+## Section 3: Session Screen Verification (Phase 22 fixes)
+
+**Purpose:** Verify callback cleanup on session leave (SESS-01)
+
+### Test Steps
+
+1. **Join Session**
+   - Join any session
+   - Wait for session screen to fully load
+
+2. **Leave Session**
+   - Click the leave button
+   - Navigate to dashboard
+
+3. **Check Console**
+   - Open browser console (F12 > Console)
+   - Look for any warnings about duplicate callbacks
+   - Look for any "cleanup" or "unregister" errors
+
+4. **Rejoin Session**
+   - Join the same or different session
+   - Verify app works normally
+
+5. **Verify No Duplicate Callbacks**
+   - Check console for "already registered" warnings
+   - Check for duplicate WebSocket event handlers
+
+### Expected Results
+
+| Check | Expected | Actual |
+|-------|----------|--------|
+| Clean leave (no errors) | Yes | |
+| Rejoin works normally | Yes | |
+| No duplicate callback warnings | Yes | |
+| Console errors | None | |
+
+**Section 3 Pass:** [ ]
+
+---
+
+## Section 4: 15-Minute Stability Test (VRFY-01)
+
+**Purpose:** Verify app remains stable during extended session use
+
+### Test Steps
+
+1. **Join Session**
+   - Join any active session
+   - Note start time: ______
+
+2. **Perform Repeated Actions**
+   - Open/close chat window: 5 times
+   - Show/hide VU meters (if available): 5 times
+   - Leave and rejoin session: 3 times
+   - Send chat messages: 10 messages
+
+3. **Wait and Observe**
+   - Keep session active for 15+ minutes
+   - Check for app responsiveness every 5 minutes:
+     - 5 min: Responsive? [ ]
+     - 10 min: Responsive? [ ]
+     - 15 min: Responsive? [ ]
+
+4. **Final Check**
+   - Note end time: ______
+   - Total duration: ______ minutes
+   - App responsive at end: [ ]
+
+### Expected Results
+
+| Check | Expected | Actual |
+|-------|----------|--------|
+| No freezes | Yes | |
+| No memory alerts | Yes | |
+| App responsive throughout | Yes | |
+| UI renders correctly | Yes | |
+
+**Section 4 Pass:** [ ]
+
+---
+
+## Section 5: Memory Growth Check (VRFY-02)
+
+**Purpose:** Verify memory doesn't grow unbounded during usage
+
+### Test Steps
+
+1. **Open Performance Monitor**
+   - Chrome DevTools > More tools > Performance monitor
+   - Note initial JS heap size: ______ MB
+
+2. **Record Baseline**
+   - Wait 30 seconds for app to stabilize
+   - Record baseline heap size: ______ MB
+
+3. **Perform Test Actions**
+   - Complete all actions from Section 4 (15-minute test)
+   - OR: At minimum, perform:
+     - 5 chat open/close cycles
+     - 5 VU meter visibility toggles
+     - 3 session leave/rejoin cycles
+
+4. **Take Heap Snapshot**
+   - DevTools > Memory tab > Take heap snapshot
+   - Note heap snapshot size: ______ MB
+
+5. **Analyze Growth**
+   - Calculate growth: (Final - Baseline) = ______ MB
+   - Growth percentage: ______%
+   - Expected: < 50% growth, heap should stabilize
+
+### Expected Results
+
+| Check | Expected | Actual |
+|-------|----------|--------|
+| Initial heap size | < 200 MB | |
+| Final heap size | < 300 MB | |
+| Growth < 50% | Yes | |
+| Heap stabilizes | Yes | |
+
+**Section 5 Pass:** [ ]
+
+---
+
+## Verification Results Summary
+
+| Section | Status | Notes |
+|---------|--------|-------|
+| Quick Verification | | |
+| Section 1: VU Meters | | |
+| Section 2: Chat Memory | | |
+| Section 3: Session Callbacks | | |
+| Section 4: 15-min Stability | | |
+| Section 5: Memory Growth | | |
+
+**Overall UAT Status:** [ ] PASS / [ ] FAIL
+
+**Verifier:** ______________________
+
+**Date:** ______________________
+
+**Notes:**
+
+---
+
+## Troubleshooting
+
+If any section fails:
+
+### VU Meter Issues
+- Check React DevTools for VuContext
+- Look for mixer IDs that don't correspond to active tracks
+- Review `useVuHelpers.js` removeVuState function
+
+### Chat Issues
+- Verify Redux DevTools shows proper state structure
+- Check clearAllMessages is called on session leave
+- Review `sessionChatSlice.js` for bounded array logic
+
+### Session Callback Issues
+- Check console for "unregister" related errors
+- Verify cleanup effect runs on unmount
+- Review `JKSessionScreen.js` for registeredCallbacksRef usage
+
+### Memory Growth Issues
+- Take multiple heap snapshots to identify retained objects
+- Look for arrays/objects that grow without bound
+- Check for detached DOM nodes in memory snapshot
+
+---
+
+*UAT Template Version: 1.0*
+*Created: 2026-02-10*
+*For: v1.4 Memory Leak Prevention Milestone*