diff --git a/Userland/Libraries/LibWeb/Streams/ReadableStreamDefaultReader.cpp b/Userland/Libraries/LibWeb/Streams/ReadableStreamDefaultReader.cpp
index 34a0b78786..a9677644f9 100644
--- a/Userland/Libraries/LibWeb/Streams/ReadableStreamDefaultReader.cpp
+++ b/Userland/Libraries/LibWeb/Streams/ReadableStreamDefaultReader.cpp
@@ -86,7 +86,7 @@ void ReadLoopReadRequest::on_chunk(JS::Value chunk)
     auto const& buffer = array.viewed_array_buffer()->buffer();
 
     // 2. Append the bytes represented by chunk to bytes.
-    m_bytes.append(buffer);
+    m_byte_chunks.append(buffer);
 
     // FIXME: As the spec suggests, implement this non-recursively - instead of directly. It is not too big of a deal currently
     //        as we enqueue the entire blob buffer in one go, meaning that we only recurse a single time. Once we begin queuing
@@ -104,7 +104,7 @@ void ReadLoopReadRequest::on_chunk(JS::Value chunk)
 void ReadLoopReadRequest::on_close()
 {
     // 1. Call successSteps with bytes.
-    m_success_steps(m_bytes);
+    m_success_steps(m_byte_chunks);
 }
 
 // error steps, given e
@@ -206,8 +206,12 @@ WebIDL::ExceptionOr<JS::NonnullGCPtr<WebIDL::Promise>> ReadableStreamDefaultRead
 
     auto promise = WebIDL::create_promise(realm);
 
-    auto success_steps = [promise, &realm](ByteBuffer bytes) {
-        auto buffer = JS::ArrayBuffer::create(realm, move(bytes));
+    auto success_steps = [promise, &realm](Vector<ByteBuffer> const& byte_chunks) {
+        ByteBuffer concatenated_byte_chunks;
+        for (auto const& chunk : byte_chunks)
+            concatenated_byte_chunks.append(chunk);
+
+        auto buffer = JS::ArrayBuffer::create(realm, move(concatenated_byte_chunks));
         WebIDL::resolve_promise(realm, promise, buffer);
     };
 
diff --git a/Userland/Libraries/LibWeb/Streams/ReadableStreamDefaultReader.h b/Userland/Libraries/LibWeb/Streams/ReadableStreamDefaultReader.h
index 4b8531fb00..78c3d8e0a4 100644
--- a/Userland/Libraries/LibWeb/Streams/ReadableStreamDefaultReader.h
+++ b/Userland/Libraries/LibWeb/Streams/ReadableStreamDefaultReader.h
@@ -36,7 +36,7 @@ class ReadLoopReadRequest final : public ReadRequest {
 
 public:
     // successSteps, which is an algorithm accepting a byte sequence
-    using SuccessSteps = JS::SafeFunction<void(ByteBuffer)>;
+    using SuccessSteps = JS::SafeFunction<void(Vector<ByteBuffer> const&)>;
 
     // failureSteps, which is an algorithm accepting a JavaScript value
     using FailureSteps = JS::SafeFunction<void(JS::Value error)>;
@@ -55,7 +55,7 @@ private:
     JS::VM& m_vm;
     JS::NonnullGCPtr<JS::Realm> m_realm;
     JS::NonnullGCPtr<ReadableStreamDefaultReader> m_reader;
-    ByteBuffer m_bytes;
+    Vector<ByteBuffer> m_byte_chunks;
     SuccessSteps m_success_steps;
     FailureSteps m_failure_steps;
 };