--- a/src/network/access/qhttp2protocolhandler.cpp
+++ b/src/network/access/qhttp2protocolhandler.cpp
@@ -371,12 +371,12 @@ bool QHttp2ProtocolHandler::sendRequest(
         }
     }
 
-    if (!prefaceSent && !sendClientPreface())
-        return false;
-
     if (!requests.size())
         return true;
 
+    if (!prefaceSent && !sendClientPreface())
+        return false;
+
     m_channel->state = QHttpNetworkConnectionChannel::WritingState;
     // Check what was promised/pushed, maybe we do not have to send a request
     // and have a response already?
--- a/src/network/access/qhttpnetworkconnectionchannel.cpp	2020-10-27 09:02:11.000000000 +0100
+++ b/src/network/access/qhttpnetworkconnectionchannel.cpp	2024-08-16 22:36:07.819945304 +0200
@@ -255,6 +255,10 @@
 bool QHttpNetworkConnectionChannel::sendRequest()
 {
     Q_ASSERT(!protocolHandler.isNull());
+    if (waitingForPotentialAbort) {
+        needInvokeSendRequest = true;
+        return false; // this return value is unused
+    }
     return protocolHandler->sendRequest();
 }
 
@@ -270,18 +274,27 @@
         Q_ASSERT(!protocolHandler.isNull());
         if (reply)
             protocolHandler->sendRequest();
+            sendRequest();
     }, Qt::ConnectionType::QueuedConnection);
 }
 
 void QHttpNetworkConnectionChannel::_q_receiveReply()
 {
     Q_ASSERT(!protocolHandler.isNull());
+    if (waitingForPotentialAbort) {
+        needInvokeReceiveReply = true;
+        return;
+    }
     protocolHandler->_q_receiveReply();
 }
 
 void QHttpNetworkConnectionChannel::_q_readyRead()
 {
     Q_ASSERT(!protocolHandler.isNull());
+    if (waitingForPotentialAbort) {
+        needInvokeReadyRead = true;
+        return;
+    }
     protocolHandler->_q_readyRead();
 }
 
@@ -1299,6 +1312,27 @@
     }
 }
 
+void QHttpNetworkConnectionChannel::checkAndResumeCommunication()
+{
+    Q_ASSERT(connection->connectionType() == QHttpNetworkConnection::ConnectionTypeHTTP2
+             || connection->connectionType() == QHttpNetworkConnection::ConnectionTypeHTTP2Direct);
+
+    // Because HTTP/2 requires that we send a SETTINGS frame as the first thing we do, and respond
+    // to a SETTINGS frame with an ACK, we need to delay any handling until we can ensure that any
+    // effects from emitting encrypted() have been processed.
+    // This function is called after encrypted() was emitted, so check for changes.
+
+    if (!reply && spdyRequestsToSend.isEmpty())
+        abort();
+    waitingForPotentialAbort = false;
+    if (needInvokeReadyRead)
+        _q_readyRead();
+    if (needInvokeReceiveReply)
+        _q_receiveReply();
+    if (needInvokeSendRequest)
+        sendRequest();
+}
+
 void QHttpNetworkConnectionChannel::requeueSpdyRequests()
 {
     QList<HttpMessagePair> spdyPairs = spdyRequestsToSend.values();
--- a/src/network/access/qhttpnetworkconnectionchannel_p.h	2020-10-27 09:02:11.000000000 +0100
+++ b/src/network/access/qhttpnetworkconnectionchannel_p.h	2024-08-16 22:40:50.519943219 +0200
@@ -107,6 +107,10 @@
     QAbstractSocket *socket;
     bool ssl;
     bool isInitialized;
+    bool waitingForPotentialAbort = false;
+    bool needInvokeReceiveReply = false;
+    bool needInvokeReadyRead = false;
+    bool needInvokeSendRequest = false;
     ChannelState state;
     QHttpNetworkRequest request; // current request, only used for HTTP
     QHttpNetworkReply *reply; // current reply for this request, only used for HTTP
@@ -187,6 +191,8 @@
     void closeAndResendCurrentRequest();
     void resendCurrentRequest();
 
+    void checkAndResumeCommunication();
+
     bool isSocketBusy() const;
     bool isSocketWriting() const;
     bool isSocketWaiting() const;