diff --git a/tests/auto/network/access/http2/http2srv.cpp b/tests/auto/network/access/http2/http2srv.cpp
index b52ea5527bd..00c7669b38f 100644
--- a/tests/auto/network/access/http2/http2srv.cpp
+++ b/tests/auto/network/access/http2/http2srv.cpp
@@ -191,6 +191,9 @@ void Http2Server::sendServerSettings()
         writer.append(it.value());
         if (it.key() == Settings::INITIAL_WINDOW_SIZE_ID)
             streamRecvWindowSize = it.value();
+        if (it.key() == Settings::HEADER_TABLE_SIZE_ID) {
+            pendingMaxTableSizeUpdate = it.value();
+        }
     }
     writer.write(*socket);
     // Now, let's update our peer on a session recv window size:
@@ -669,6 +672,13 @@ void Http2Server::handleSETTINGS()
             return;
         }
 
+        // The client ACKed our setting, including the new decoder table size,
+        // so we can update it now:
+        if (pendingMaxTableSizeUpdate) {
+            decoder.setMaxDynamicTableSize(*pendingMaxTableSizeUpdate);
+            pendingMaxTableSizeUpdate.reset();
+        }
+
         waitingClientAck = false;
         emit serverSettingsAcked();
         return;
diff --git a/tests/auto/network/access/http2/http2srv.h b/tests/auto/network/access/http2/http2srv.h
index dc94318527b..c74a51bdb9d 100644
--- a/tests/auto/network/access/http2/http2srv.h
+++ b/tests/auto/network/access/http2/http2srv.h
@@ -213,6 +213,8 @@ private:
 
     bool sendTrailingHEADERS = false;
     int informationalStatusCode = 0;
+
+    std::optional<quint32> pendingMaxTableSizeUpdate;
 protected slots:
     void ignoreErrorSlot();
 };
diff --git a/tests/auto/network/access/http2/tst_http2.cpp b/tests/auto/network/access/http2/tst_http2.cpp
index d80a7fbc656..d7a36f61274 100644
--- a/tests/auto/network/access/http2/tst_http2.cpp
+++ b/tests/auto/network/access/http2/tst_http2.cpp
@@ -113,6 +113,8 @@ private slots:
 
     void limitedConcurrentStreamsAllowed();
 
+    void maxHeaderTableSize();
+
 protected slots:
     // Slots to listen to our in-process server:
     void serverStarted(quint16 port);
@@ -1637,6 +1639,55 @@ void tst_Http2::limitedConcurrentStreamsAllowed()
     QCOMPARE(finishedCount, TotalRequests);
 }
 
+void tst_Http2::maxHeaderTableSize()
+{
+    clearHTTP2State();
+    serverPort = 0;
+
+    H2Type connectionType = H2Type::h2Direct;
+    RawSettings maxHeaderTableSize{ { Http2::Settings::HEADER_TABLE_SIZE_ID, 0 } };
+    ServerPtr targetServer(newServer(maxHeaderTableSize, connectionType));
+
+    QMetaObject::invokeMethod(targetServer.data(), "startServer", Qt::QueuedConnection);
+    runEventLoop();
+
+    QVERIFY(serverPort != 0);
+
+    nRequests = 1;
+
+    const auto url = requestUrl(connectionType);
+    QNetworkRequest request(url);
+    request.setAttribute(QNetworkRequest::Http2DirectAttribute, true);
+
+    constexpr int extraRequests = 5;
+    std::array<std::unique_ptr<QNetworkReply>, extraRequests> replies;
+    for (qint32 i = 0; i < 1 + extraRequests; ++i) {
+        for (qint32 j = 0; j < 100; ++j) {
+            request.setRawHeader("x-test" + QByteArray::number(j),
+                                 "Hello World" + QByteArray::number(i));
+        }
+        std::unique_ptr<QNetworkReply> reply{ manager->get(request) };
+        reply->ignoreSslErrors();
+        connect(reply.get(), &QNetworkReply::finished, this, &tst_Http2::replyFinished);
+
+        if (i == 0) {
+            runEventLoop();
+            STOP_ON_FAILURE
+            QCOMPARE(reply->error(), QNetworkReply::NoError);
+            nRequests = extraRequests;
+        } else {
+            replies[i - 1] = std::move(reply);
+        }
+    }
+
+    runEventLoop();
+    STOP_ON_FAILURE
+
+    QCOMPARE(nRequests, 0);
+    for (const auto &reply : replies)
+        QCOMPARE(reply->error(), QNetworkReply::NoError);
+}
+
 void tst_Http2::serverStarted(quint16 port)
 {
     serverPort = port;