fix(replay): Reuse the in-flight feedback flush on form remount

A remount while the first open's captureReplay is still pending previously
replaced the in-flight flush with a fresh one, discarding the pending upload so
submit could link nothing. Keep the in-flight flush and only start a new one
once the previous has settled, alongside the existing carry-forward of a
completed upload.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: antonis

packages/core/src/js/replay/mobilereplay.ts

@@ -524,12 +524,18 @@ export const mobileReplayIntegration = (initOptions: MobileReplayOptions = defau
   }
 
   // Start uploading the buffer when the widget opens. Read the buffer id first (before capture may
-  // restart buffering) so the id we link matches what this flush uploads. Each open starts a fresh
-  // flush but carries forward an id a previous open already uploaded, so a remount (e.g. the
-  // screenshot flow closes and reopens the form) whose own flush uploads nothing still links it.
-  // Wrapped: a synchronous bridge throw must not propagate out of the widget's `componentDidMount`.
+  // restart buffering) so the id we link matches what this flush uploads. A remount (e.g. the
+  // screenshot flow closes and reopens the form) reuses a flush that is still in flight, and
+  // otherwise carries forward an id a previous open already uploaded, so neither a pending nor a
+  // completed upload is discarded. Wrapped: a synchronous bridge throw must not propagate out of
+  // the widget's `componentDidMount`.
   function flushReplayForFeedbackWidget(): void {
     try {
+      // A flush from an earlier open in the same flow is still uploading: keep it rather than
+      // starting another, so its pending upload isn't discarded.
+      if (feedbackReplayFlush && !feedbackReplayFlush.resolved) {
+        return;
+      }
       const carried = feedbackReplayFlush?.resolved ? feedbackReplayFlush.id : null;
       const flush: { openId: string | null; id: string | null; resolved: boolean } = {
         openId: NATIVE.getCurrentReplayId() ?? carried,

packages/core/test/replay/mobilereplay.test.ts

@@ -1553,6 +1553,33 @@ describe('Mobile Replay Integration', () => {
       expect(feedback.contexts.feedback.replay_id).toBe('first-id');
     });
 
+    it('keeps the in-flight open flush when the form remounts before it settles', async () => {
+      // The first open's capture is still pending when the form remounts.
+      let resolveFirst!: (v: string | null) => void;
+      mockCaptureReplay.mockReturnValueOnce(
+        new Promise<string | null>(resolve => {
+          resolveFirst = resolve;
+        }),
+      );
+      mockGetCurrentReplayId.mockReturnValue(null);
+      const integration = mobileReplayIntegration();
+      integration.setup?.(mockClient);
+
+      getOpenFeedbackWidget()(); // first open, flush in flight
+      getOpenFeedbackWidget()(); // remount before the first settles
+
+      // The remount reuses the in-flight flush instead of starting another.
+      expect(mockCaptureReplay).toHaveBeenCalledTimes(1);
+
+      resolveFirst('in-flight-id');
+      await flushAsync();
+
+      const feedback = makeFeedbackEvent('widget');
+      getBeforeSendFeedback()(feedback, { includeReplay: true });
+
+      expect(feedback.contexts.feedback.replay_id).toBe('in-flight-id');
+    });
+
     it('does not propagate a synchronous bridge error when the widget opens', () => {
       const integration = mobileReplayIntegration();
       integration.setup?.(mockClient);