diff --git a/src/network/access/qnetworkreplyhttpimpl.cpp b/src/network/access/qnetworkreplyhttpimpl.cpp
index b7626cd060c..a753639b14a 100644
--- a/src/network/access/qnetworkreplyhttpimpl.cpp
+++ b/src/network/access/qnetworkreplyhttpimpl.cpp
@@ -1329,6 +1329,11 @@ void QNetworkReplyHttpImplPrivate::replyDownloadMetaData(const QList<QPair<QByte
     q->setAttribute(QNetworkRequest::HttpPipeliningWasUsedAttribute, pu);
     q->setAttribute(QNetworkRequest::Http2WasUsedAttribute, h2Used);
 
+    // A user having manually defined which encodings they accept is, for
+    // somwehat unknown (presumed legacy compatibility) reasons treated as
+    // disabling our decompression:
+    const bool autoDecompress = request.rawHeader("accept-encoding").isEmpty();
+    const bool shouldDecompress = isCompressed && autoDecompress;
     // reconstruct the HTTP header
     QList<QPair<QByteArray, QByteArray> > headerMap = hm;
     QList<QPair<QByteArray, QByteArray> >::ConstIterator it = headerMap.constBegin(),
@@ -1342,7 +1347,7 @@ void QNetworkReplyHttpImplPrivate::replyDownloadMetaData(const QList<QPair<QByte
         if (it->first.toLower() == "location")
             value.clear();
 
-        if (isCompressed && !decompressHelper.isValid()
+        if (shouldDecompress && !decompressHelper.isValid()
             && it->first.compare("content-encoding", Qt::CaseInsensitive) == 0) {
 
             if (!synchronous) // with synchronous all the data is expected to be handled at once
diff --git a/tests/auto/network/access/qnetworkreply/tst_qnetworkreply.cpp b/tests/auto/network/access/qnetworkreply/tst_qnetworkreply.cpp
index 1ab3cb97f5a..e653ebf6986 100644
--- a/tests/auto/network/access/qnetworkreply/tst_qnetworkreply.cpp
+++ b/tests/auto/network/access/qnetworkreply/tst_qnetworkreply.cpp
@@ -9669,25 +9669,53 @@ void tst_QNetworkReply::contentEncoding_data()
     QTest::addColumn<QByteArray>("encoding");
     QTest::addColumn<QByteArray>("body");
     QTest::addColumn<QByteArray>("expected");
+    QTest::addColumn<bool>("decompress");
 
+    const QByteArray helloWorld = "hello world";
+
+    const QByteArray gzipBody = QByteArray::fromBase64("H4sIAAAAAAAAA8tIzcnJVyjPL8pJAQCFEUoNCwAAAA==");
     QTest::newRow("gzip-hello-world")
             << QByteArray("gzip")
-            << QByteArray::fromBase64("H4sIAAAAAAAAA8tIzcnJVyjPL8pJAQCFEUoNCwAAAA==")
-            << QByteArray("hello world");
+            << gzipBody
+            << helloWorld
+            << true;
+    QTest::newRow("gzip-hello-world-no-decompress")
+            << QByteArray("gzip")
+            << gzipBody
+            << helloWorld
+            << false;
+    const QByteArray deflateBody = QByteArray::fromBase64("eJzLSM3JyVcozy/KSQEAGgsEXQ==");
     QTest::newRow("deflate-hello-world")
-            << QByteArray("deflate") << QByteArray::fromBase64("eJzLSM3JyVcozy/KSQEAGgsEXQ==")
-            << QByteArray("hello world");
+            << QByteArray("deflate") << deflateBody
+            << helloWorld
+            << true;
+    QTest::newRow("deflate-hello-world-no-decompress")
+            << QByteArray("deflate") << deflateBody
+            << helloWorld
+            << false;
 
 #if QT_CONFIG(brotli)
+    const QByteArray brotliBody = QByteArray::fromBase64("DwWAaGVsbG8gd29ybGQD");
     QTest::newRow("brotli-hello-world")
-            << QByteArray("br") << QByteArray::fromBase64("DwWAaGVsbG8gd29ybGQD")
-            << QByteArray("hello world");
+            << QByteArray("br") << brotliBody
+            << helloWorld
+            << true;
+    QTest::newRow("brotli-hello-world-no-decompress")
+            << QByteArray("br") << brotliBody
+            << helloWorld
+            << false;
 #endif
 
 #if defined(QT_BUILD_INTERNAL) && QT_CONFIG(zstd)
+    const QByteArray zstdBody = QByteArray::fromBase64("KLUv/QRYWQAAaGVsbG8gd29ybGRoaR6y");
     QTest::newRow("zstandard-hello-world")
-            << QByteArray("zstd") << QByteArray::fromBase64("KLUv/QRYWQAAaGVsbG8gd29ybGRoaR6y")
-            << QByteArray("hello world");
+            << QByteArray("zstd") << zstdBody
+            << helloWorld
+            << true;
+    QTest::newRow("zstandard-hello-world-no-decompress")
+            << QByteArray("zstd") << zstdBody
+            << helloWorld
+            << false;
 #else
     qDebug("Note: ZStandard testdata is only available for developer builds.");
 #endif
@@ -9697,12 +9725,19 @@ void tst_QNetworkReply::contentEncoding()
 {
     QFETCH(QByteArray, encoding);
     QFETCH(QByteArray, body);
+    QFETCH(bool, decompress);
     QString header("HTTP/1.0 200 OK\r\nContent-Encoding: %1\r\nContent-Length: %2\r\n\r\n");
     header = header.arg(encoding, QString::number(body.size()));
 
     MiniHttpServer server(header.toLatin1() + body);
 
     QNetworkRequest request(QUrl("http://localhost:" + QString::number(server.serverPort())));
+    if (!decompress) {
+        // This disables decompression of the received content:
+        request.setRawHeader("Accept-Encoding", QLatin1String("%1").arg(encoding).toLatin1());
+        // This disables the zerocopy optimization
+        request.setAttribute(QNetworkRequest::MaximumDownloadBufferSizeAttribute, 0);
+    }
     QNetworkReplyPtr reply(manager.get(request));
 
     QVERIFY2(waitForFinish(reply) == Success, msgWaitForFinished(reply));
@@ -9723,10 +9758,14 @@ void tst_QNetworkReply::contentEncoding()
         QVERIFY2(list.contains(encoding), acceptedEncoding.data());
     }
 
-    QFETCH(QByteArray, expected);
-
-    QCOMPARE(reply->bytesAvailable(), expected.size());
-    QCOMPARE(reply->readAll(), expected);
+    if (decompress) {
+        QFETCH(QByteArray, expected);
+        QCOMPARE(reply->bytesAvailable(), expected.size());
+        QCOMPARE(reply->readAll(), expected);
+    } else {
+        QCOMPARE(reply->bytesAvailable(), body.size());
+        QCOMPARE(reply->readAll(), body);
+    }
 }
 
 void tst_QNetworkReply::contentEncodingBigPayload_data()