diff --git a/src/api/api.cc b/src/api/api.cc
index da477c87bb6c..72564037c612 100644
--- a/src/api/api.cc
+++ b/src/api/api.cc
@@ -10966,6 +10966,7 @@ void RecordReplayOnExceptionUnwind(Isolate* isolate) {
     return;
 
   Handle<Object> exception(isolate->pending_exception(), isolate);
+  recordreplay::Print("[PRO-1150] RecordReplayOnExceptionUnwind A %d", isolate->is_catchable_by_javascript(*exception));
   if (!isolate->is_catchable_by_javascript(*exception))
     return;
 
@@ -10979,24 +10980,44 @@ void RecordReplayOnExceptionUnwind(Isolate* isolate) {
       std::vector<FrameSummary> frames;
       it.frame()->Summarize(&frames);
       if (!frames.empty()) { // There might not always be a frame due to RUN-1920.
-        auto& summary = frames.back().AsJavaScript();
-        Handle<SharedFunctionInfo> shared(summary.function()->shared(), isolate);
-        Handle<Object> script(shared->script(), isolate);
-        if (script->IsScript()) {
-          Handle<Script> casted_script = Handle<Script>::cast(script);
-          if (!RecordReplayHasRegisteredScript(*casted_script)) {
-            // Don't repor errors from unregistered.
-            return;
+        bool hasFrameFromRegisteredScript = false;
+        for (int i = static_cast<int>(frames.size()) - 1; i >= 0; i--) {
+          FrameSummary::JavaScriptFrameSummary const& summary = frames[i].AsJavaScript();
+          Handle<SharedFunctionInfo> shared(summary.function()->shared(), isolate);
+          Handle<Object> s(shared->script(), isolate);
+          if (s->IsScript()) {
+            Handle<Script> script = Handle<Script>::cast(s);
+
+            std::string script_name = script->name().IsString()
+              ? String::cast(script->name()).ToCString().get()
+              : "(anonymous script)";
+            recordreplay::Assert("[PRO-1105] RecordReplayOnExceptionUnwind %d/%d id=%d fun=%s script=%s",
+                                 i,
+                                 static_cast<int>(frames.size()),
+                                 script->id(),
+                                 SharedFunctionInfo::DebugName(shared),
+                                 script_name.c_str());
+            if (!RecordReplayHasRegisteredScript(*script)) {
+              hasFrameFromRegisteredScript = true;
+              break;
+            }
           }
         }
+        if (!hasFrameFromRegisteredScript) {
+          // Don't report errors from unregistered.
+          return;
+        }
       }
     }
   }
 
+  recordreplay::Print("[PRO-1150] RecordReplayOnExceptionUnwind B");
+
   isolate->clear_pending_exception();
   Handle<Object> message(isolate->pending_message(), isolate);
   isolate->clear_pending_message();
   Handle<Object> scheduledException;
+  recordreplay::Print("[PRO-1150] RecordReplayOnExceptionUnwind C %d", isolate->has_scheduled_exception());
   if (isolate->has_scheduled_exception()) {
     scheduledException = Handle<Object>(isolate->scheduled_exception(), isolate);
     isolate->clear_scheduled_exception();
@@ -11009,6 +11030,7 @@ void RecordReplayOnExceptionUnwind(Isolate* isolate) {
   CHECK(!isolate->has_pending_exception());
   isolate->set_pending_exception(*exception);
   isolate->set_pending_message(*message);
+  recordreplay::Print("[PRO-1150] RecordReplayOnExceptionUnwind D %d", scheduledException.is_null());
   if (!scheduledException.is_null()) {
     isolate->set_scheduled_exception(*scheduledException);
   }
diff --git a/src/codegen/compiler.cc b/src/codegen/compiler.cc
index dd7473e73c88..b5b52345658b 100644
--- a/src/codegen/compiler.cc
+++ b/src/codegen/compiler.cc
@@ -414,6 +414,8 @@ ScriptOriginOptions OriginOptionsForEval(
       is_opaque = true;
     }
   }
+  recordreplay::Print("ScriptOriginOptions OriginOptionsForEval %d",
+                       is_shared_cross_origin);
   return ScriptOriginOptions(is_shared_cross_origin, is_opaque);
 }
 
diff --git a/src/execution/frames.cc b/src/execution/frames.cc
index 5d613e69705e..74ae94721273 100644
--- a/src/execution/frames.cc
+++ b/src/execution/frames.cc
@@ -249,6 +249,9 @@ int StackTraceFrameIterator::FrameFunctionCount() const {
   return static_cast<int>(infos.size());
 }
 
+extern bool RecordReplayHasRegisteredScript(Script script);
+extern "C" void V8RecordReplayGetCurrentJSStack(std::string* js_stack);
+
 FrameSummary StackTraceFrameIterator::GetTopValidFrame() const {
   DCHECK(!done());
   // Like FrameSummary::GetTop, but additionally observes
@@ -256,10 +259,35 @@ FrameSummary StackTraceFrameIterator::GetTopValidFrame() const {
   std::vector<FrameSummary> frames;
   frame()->Summarize(&frames);
   if (is_javascript()) {
+    
+    std::string js_stack;
+    V8RecordReplayGetCurrentJSStack(&js_stack);
+    recordreplay::Trace("[PRO-1150] StackTraceFrameIterator::GetTopValidFrame size %d %s",
+                        static_cast<int>(frames.size()),
+                        js_stack.c_str());
+    base::Optional<FrameSummary> normal_rv;
     for (int i = static_cast<int>(frames.size()) - 1; i >= 0; i--) {
       if (!IsValidJSFunction(*frames[i].AsJavaScript().function())) continue;
+      recordreplay::Print("[PRO-1150] StackTraceFrameIterator::GetTopValidFrame 1");
+      if (recordreplay::IsRecordingOrReplaying("StackTraceFrameIterator::GetTopValidFrame") &&
+        !recordreplay::AreEventsDisallowed()) {
+        // [PRO-1105] Skip our own (or generally, divergent) scripts.
+        if (!RecordReplayHasRegisteredScript(*Handle<Script>::cast(frames[i].script()))) {
+          recordreplay::Print("[PRO-1150] StackTraceFrameIterator::GetTopValidFrame i %d script_id %d continue", i, Handle<Script>::cast(frames[i].script())->id());
+          if (!normal_rv.has_value()) {
+            normal_rv.emplace(std::move(frames[i]));
+          }
+          continue;
+        }
+        recordreplay::Print("[PRO-1150] StackTraceFrameIterator::GetTopValidFrame i %d script_id %d return", i, Handle<Script>::cast(frames[i].script())->id());
+      }
       return frames[i];
     }
+    if (normal_rv.has_value()) {
+      // if all frames belongs to unregistered scripts return the first one like that
+      recordreplay::Print("[PRO-1150] StackTraceFrameIterator::GetTopValidFrame returning fallback unregistered frame");
+      return *normal_rv;
+    }
     UNREACHABLE();
   }
 #if V8_ENABLE_WEBASSEMBLY
diff --git a/src/execution/isolate.cc b/src/execution/isolate.cc
index 60246e2e78c2..78a436c4ce13 100644
--- a/src/execution/isolate.cc
+++ b/src/execution/isolate.cc
@@ -2604,6 +2604,7 @@ bool Isolate::ComputeLocationFromException(MessageLocation* target,
   if (!script->IsScript()) return false;
 
   Handle<Script> cast_script(Script::cast(*script), this);
+
   *target = MessageLocation(cast_script, start_pos_value, end_pos_value);
   return true;
 }
@@ -2639,6 +2640,10 @@ bool Isolate::ComputeLocationFromDetailedStackTrace(MessageLocation* target,
                               this);
   const int pos = StackFrameInfo::GetSourcePosition(info);
   *target = MessageLocation(handle(info->script(), this), pos, pos + 1);
+  
+  recordreplay::AssertMaybeEventsDisallowed(
+    "[PRO-1150] Isolate::ComputeLocationFromDetailedStackTrace %d %d",
+    info->script().id(), pos);
   return true;
 }
 
diff --git a/src/execution/messages.cc b/src/execution/messages.cc
index 8bd6fe99a3df..b926a8a0d558 100644
--- a/src/execution/messages.cc
+++ b/src/execution/messages.cc
@@ -32,7 +32,11 @@ MessageLocation::MessageLocation(Handle<Script> script, int start_pos,
     : script_(script),
       start_pos_(start_pos),
       end_pos_(end_pos),
-      bytecode_offset_(-1) {}
+      bytecode_offset_(-1) {
+  recordreplay::Print(
+    "[PRO-1150] MessageLocation::MessageLocation A %d %d %d",
+    script->id(), start_pos, end_pos);
+}
 
 MessageLocation::MessageLocation(Handle<Script> script, int start_pos,
                                  int end_pos, Handle<SharedFunctionInfo> shared)
@@ -40,7 +44,11 @@ MessageLocation::MessageLocation(Handle<Script> script, int start_pos,
       start_pos_(start_pos),
       end_pos_(end_pos),
       bytecode_offset_(-1),
-      shared_(shared) {}
+      shared_(shared) {
+  recordreplay::Print(
+    "[PRO-1150] MessageLocation::MessageLocation B %d %d %d",
+    script->id(), start_pos, end_pos);
+}
 
 MessageLocation::MessageLocation(Handle<Script> script,
                                  Handle<SharedFunctionInfo> shared,
@@ -49,10 +57,17 @@ MessageLocation::MessageLocation(Handle<Script> script,
       start_pos_(-1),
       end_pos_(-1),
       bytecode_offset_(bytecode_offset),
-      shared_(shared) {}
+      shared_(shared) {
+  recordreplay::Print(
+    "[PRO-1150] MessageLocation::MessageLocation C %d",
+    script->id());
+}
 
 MessageLocation::MessageLocation()
-    : start_pos_(-1), end_pos_(-1), bytecode_offset_(-1) {}
+    : start_pos_(-1), end_pos_(-1), bytecode_offset_(-1) {
+  recordreplay::Print(
+    "[PRO-1150] MessageLocation::MessageLocation D");
+}
 
 // If no message listeners have been registered this one is called
 // by default.
@@ -438,7 +453,14 @@ MaybeHandle<Object> ErrorUtils::FormatStackTrace(Isolate* isolate,
     }
   }
 
-  return builder.Finish();
+  MaybeHandle<String> rv = builder.Finish();
+  if (recordreplay::IsRecordingOrReplaying("ErrorUtils::FormatStackTrace")) {
+    // [PRO-1150] Replay error stack.
+    std::string str = rv.ToHandleChecked()->ToCString().get();
+    recordreplay::RecordReplayString("ErrorUtils::FormatStackTrace", str);
+    rv = isolate->factory()->NewStringFromUtf8(base::CStrVector(str.c_str()));
+  }
+  return rv;
 }
 
 Handle<String> MessageFormatter::Format(Isolate* isolate, MessageTemplate index,
diff --git a/src/objects/call-site-info.cc b/src/objects/call-site-info.cc
index 4b57bcbfdf48..c70918989892 100644
--- a/src/objects/call-site-info.cc
+++ b/src/objects/call-site-info.cc
@@ -553,6 +553,10 @@ bool CallSiteInfo::ComputeLocation(Handle<CallSiteInfo> info,
   if (!shared->IsSubjectToDebugging()) return false;
   Handle<Script> script(Script::cast(shared->script()), isolate);
   if (script->source().IsUndefined()) return false;
+  
+  recordreplay::AssertMaybeEventsDisallowed(
+    "[PRO-1150] CallSiteInfo::ComputeLocation %d",
+    script->id());
   if (info->flags() & kIsSourcePositionComputed ||
       (shared->HasBytecodeArray() &&
        shared->GetBytecodeArray(isolate).HasSourcePositionTable())) {
diff --git a/src/objects/script-inl.h b/src/objects/script-inl.h
index 4d1af1104a70..417d6b9cb21a 100644
--- a/src/objects/script-inl.h
+++ b/src/objects/script-inl.h
@@ -155,6 +155,8 @@ void Script::set_is_repl_mode(bool value) {
 }
 
 ScriptOriginOptions Script::origin_options() {
+  recordreplay::Print("ScriptOriginOptions Script::origin_options %d",
+                       OriginOptionsBits::decode(flags()));
   return ScriptOriginOptions(OriginOptionsBits::decode(flags()));
 }
 void Script::set_origin_options(ScriptOriginOptions origin_options) {
diff --git a/src/runtime/runtime-internal.cc b/src/runtime/runtime-internal.cc
index 92eb39d9aa97..1ddaa51b6194 100644
--- a/src/runtime/runtime-internal.cc
+++ b/src/runtime/runtime-internal.cc
@@ -195,6 +195,10 @@ RUNTIME_FUNCTION(Runtime_UnwindAndFindExceptionHandler) {
   // a script, try/catch block, or try/finally block. If the progress counter
   // when unwinding is the same as the last time when unwinding, this is a
   // frame unwind instead of an initial throw and we can ignore it.
+  recordreplay::Print(
+      "[PRO-1150] Runtime_UnwindAndFindExceptionHandler %d %d %d\n",
+      *gProgressCounter, gLastExceptionUnwindProgress,
+      recordreplay::AreEventsDisallowed());
   if (recordreplay::IsRecordingOrReplaying() &&
       !recordreplay::AreEventsDisallowed() &&
       IsMainThread() &&