diff --git a/Libraries/LibWeb/HTML/MessagePort.cpp b/Libraries/LibWeb/HTML/MessagePort.cpp
index 97d6a808e80..92eb0981d96 100644
--- a/Libraries/LibWeb/HTML/MessagePort.cpp
+++ b/Libraries/LibWeb/HTML/MessagePort.cpp
@@ -324,11 +324,11 @@ void MessagePort::post_message_task_steps(SerializedTransferRecord& serialize_wi
 
     // 2. Let targetRealm be finalTargetPort's relevant realm.
     auto& target_realm = relevant_realm(*final_target_port);
-    auto& target_vm = target_realm.vm();
+
+    TemporaryExecutionContext context { target_realm };
 
     // 3. Let deserializeRecord be StructuredDeserializeWithTransfer(serializeWithTransferResult, targetRealm).
-    TemporaryExecutionContext context { relevant_realm(*final_target_port) };
-    auto deserialize_record_or_error = structured_deserialize_with_transfer(target_vm, serialize_with_transfer_result);
+    auto deserialize_record_or_error = structured_deserialize_with_transfer(serialize_with_transfer_result, target_realm);
     if (deserialize_record_or_error.is_error()) {
         // If this throws an exception, catch it, fire an event named messageerror at finalTargetPort, using MessageEvent, and then return.
         auto exception = deserialize_record_or_error.release_error();
diff --git a/Libraries/LibWeb/HTML/StructuredSerialize.cpp b/Libraries/LibWeb/HTML/StructuredSerialize.cpp
index 736257d3be5..6f1566f63db 100644
--- a/Libraries/LibWeb/HTML/StructuredSerialize.cpp
+++ b/Libraries/LibWeb/HTML/StructuredSerialize.cpp
@@ -1319,9 +1319,9 @@ static WebIDL::ExceptionOr<GC::Ref<Bindings::PlatformObject>> create_transferred
 }
 
 // https://html.spec.whatwg.org/multipage/structured-data.html#structureddeserializewithtransfer
-WebIDL::ExceptionOr<DeserializedTransferRecord> structured_deserialize_with_transfer(JS::VM& vm, SerializedTransferRecord& serialize_with_transfer_result)
+WebIDL::ExceptionOr<DeserializedTransferRecord> structured_deserialize_with_transfer(SerializedTransferRecord& serialize_with_transfer_result, JS::Realm& target_realm)
 {
-    auto& target_realm = *vm.current_realm();
+    auto& vm = target_realm.vm();
 
     // 1. Let memory be an empty map.
     auto memory = DeserializationMemory(vm.heap());
diff --git a/Libraries/LibWeb/HTML/StructuredSerialize.h b/Libraries/LibWeb/HTML/StructuredSerialize.h
index 1e35a3085f2..cfa61af8f21 100644
--- a/Libraries/LibWeb/HTML/StructuredSerialize.h
+++ b/Libraries/LibWeb/HTML/StructuredSerialize.h
@@ -124,7 +124,7 @@ WebIDL::ExceptionOr<GC::Ref<JS::PrimitiveString>> deserialize_string_primitive(J
 WebIDL::ExceptionOr<GC::Ref<JS::BigInt>> deserialize_big_int_primitive(JS::VM& vm, ReadonlySpan<u32> vector, size_t& position);
 
 WebIDL::ExceptionOr<SerializedTransferRecord> structured_serialize_with_transfer(JS::VM& vm, JS::Value value, Vector<GC::Root<JS::Object>> const& transfer_list);
-WebIDL::ExceptionOr<DeserializedTransferRecord> structured_deserialize_with_transfer(JS::VM& vm, SerializedTransferRecord&);
+WebIDL::ExceptionOr<DeserializedTransferRecord> structured_deserialize_with_transfer(SerializedTransferRecord&, JS::Realm& target_realm);
 
 }
 
diff --git a/Libraries/LibWeb/HTML/Window.cpp b/Libraries/LibWeb/HTML/Window.cpp
index fa7c5f57113..a6e6d6181be 100644
--- a/Libraries/LibWeb/HTML/Window.cpp
+++ b/Libraries/LibWeb/HTML/Window.cpp
@@ -1190,9 +1190,10 @@ WebIDL::ExceptionOr<void> Window::window_post_message_steps(JS::Value message, W
         // 3. Let source be the WindowProxy object corresponding to incumbentSettings's global object (a Window object).
         auto& source = as<WindowProxy>(incumbent_settings.realm().global_environment().global_this_value());
 
+        TemporaryExecutionContext temporary_execution_context { target_realm, TemporaryExecutionContext::CallbacksEnabled::Yes };
+
         // 4. Let deserializeRecord be StructuredDeserializeWithTransfer(serializeWithTransferResult, targetRealm).
-        auto temporary_execution_context = TemporaryExecutionContext { target_realm, TemporaryExecutionContext::CallbacksEnabled::Yes };
-        auto deserialize_record_or_error = structured_deserialize_with_transfer(vm(), serialize_with_transfer_result);
+        auto deserialize_record_or_error = structured_deserialize_with_transfer(serialize_with_transfer_result, target_realm);
 
         // If this throws an exception, catch it, fire an event named messageerror at targetWindow, using MessageEvent,
         // with the origin attribute initialized to origin and the source attribute initialized to source, and then return.