From c3b17a2270a7bebabe2bd23e30c7ab4c85aec09c Mon Sep 17 00:00:00 2001
From: Gordon MacMaster <31481849+gmacmaster@users.noreply.github.com>
Date: Tue, 5 May 2026 19:31:00 -0400
Subject: [PATCH] fix: cancel active touches in onPointerCaptureLost to prevent
 zombie touch state (#16086)
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* fix: cancel active touches in onPointerCaptureLost to prevent zombie touch state (#2)

* fix: cancel active touches in onPointerCaptureLost to prevent zombie touch state

When the OS reclaims pointer capture mid-gesture (system back swipe, Alt+Tab,
  another window coming foreground), onPointerCaptureLost fired but never removed
  entries from m_activeTouches or dispatched a touchcancel to React Native JS.
  The result was a zombie active touch — RN JS believed a finger was still down,
  leaving Pressables and TouchableOpacities stuck in a pressed state until the
  next touch happened to reuse the same pointer ID and trigger the stale-touch
  cleanup in onPointerPressed.

  Fix: for each captured pointer in the lost-capture set, copy and erase the
  m_activeTouches entry before calling DispatchSynthesizedTouchCancelForActiveTouch,
  mirroring the pattern already used in onPointerPressed and onPointerReleased.
  The erase-before-dispatch ordering is required because
  DispatchSynthesizedTouchCancelForActiveTouch iterates m_activeTouches internally.

* match the m_pointerCapturingComponentTag != -1 check already used in CapturePointer

* Create react-native-windows-f47bdf2a-0807-483f-b63e-3c2c086bee92.json
---
 ...ows-f47bdf2a-0807-483f-b63e-3c2c086bee92.json |  7 +++++++
 .../Composition/CompositionEventHandler.cpp      | 16 +++++++++++++++-
 2 files changed, 22 insertions(+), 1 deletion(-)
 create mode 100644 change/react-native-windows-f47bdf2a-0807-483f-b63e-3c2c086bee92.json

diff --git a/change/react-native-windows-f47bdf2a-0807-483f-b63e-3c2c086bee92.json b/change/react-native-windows-f47bdf2a-0807-483f-b63e-3c2c086bee92.json
new file mode 100644
index 00000000000..541f74718ee
--- /dev/null
+++ b/change/react-native-windows-f47bdf2a-0807-483f-b63e-3c2c086bee92.json
@@ -0,0 +1,7 @@
+{
+  "type": "prerelease",
+  "comment": "fix: cancel active touches in onPointerCaptureLost to prevent zombie touch state",
+  "packageName": "react-native-windows",
+  "email": "gordomacmaster@gmail.com",
+  "dependentChangeType": "patch"
+}
\ No newline at end of file
diff --git a/vnext/Microsoft.ReactNative/Fabric/Composition/CompositionEventHandler.cpp b/vnext/Microsoft.ReactNative/Fabric/Composition/CompositionEventHandler.cpp
index 928ee52b407..99890b594eb 100644
--- a/vnext/Microsoft.ReactNative/Fabric/Composition/CompositionEventHandler.cpp
+++ b/vnext/Microsoft.ReactNative/Fabric/Composition/CompositionEventHandler.cpp
@@ -1092,12 +1092,26 @@ void CompositionEventHandler::onPointerCaptureLost(
   if (SurfaceId() == -1)
     return;
 
-  if (m_pointerCapturingComponentTag) {
+  if (m_pointerCapturingComponentTag != -1) {
     // copy array to avoid iterator being invalidated during deletion
     std::unordered_set<PointerId> capturedPointers = m_capturedPointers;
 
     for (auto pointerId : capturedPointers) {
       releasePointerCapture(pointerId, m_pointerCapturingComponentTag);
+
+      // Cancel any active touch for this pointer so React Native is notified that
+      // the touch ended. Without this, m_activeTouches retains a zombie entry and
+      // RN JS is never told the touch is gone — leaving Pressables stuck in a
+      // pressed state after a system-interrupted gesture (e.g. system back swipe,
+      // Alt+Tab, another window coming foreground).
+      auto activeTouch = m_activeTouches.find(pointerId);
+      if (activeTouch != m_activeTouches.end()) {
+        ActiveTouch cancelledTouchCopy = std::move(activeTouch->second);
+        m_activeTouches.erase(activeTouch);
+        if (cancelledTouchCopy.eventEmitter) {
+          DispatchSynthesizedTouchCancelForActiveTouch(cancelledTouchCopy, pointerPoint, keyModifiers);
+        }
+      }
     }
 
     m_pointerCapturingComponentTag = -1;