diff --git a/src/plugins/help/localhelpmanager.cpp b/src/plugins/help/localhelpmanager.cpp
index 07ab621ccc7..0a29750b85a 100644
--- a/src/plugins/help/localhelpmanager.cpp
+++ b/src/plugins/help/localhelpmanager.cpp
@@ -33,8 +33,10 @@
 
 #ifdef QTC_WEBENGINE_HELPVIEWER
 #include "webenginehelpviewer.h"
+#if QT_VERSION >= QT_VERSION_CHECK(5, 12, 0)
 #include <QWebEngineUrlScheme>
 #endif
+#endif
 #ifdef QTC_LITEHTML_HELPVIEWER
 #include "litehtmlhelpviewer.h"
 #endif
@@ -324,6 +326,7 @@ QVector<HelpViewerFactory> LocalHelpManager::viewerBackends()
 {
     QVector<HelpViewerFactory> result;
 #ifdef QTC_WEBENGINE_HELPVIEWER
+#if QT_VERSION >= QT_VERSION_CHECK(5, 12, 0)
     static bool schemeRegistered = false;
     if (!schemeRegistered) {
         schemeRegistered = true;
@@ -331,6 +334,7 @@ QVector<HelpViewerFactory> LocalHelpManager::viewerBackends()
         scheme.setFlags(QWebEngineUrlScheme::LocalScheme | QWebEngineUrlScheme::LocalAccessAllowed);
         QWebEngineUrlScheme::registerScheme(scheme);
     }
+#endif
     result.append(
         {kQtWebEngineBackend, tr("QtWebEngine"), []() { return new WebEngineHelpViewer; }});
 #endif