diff --git a/src/app/main.cpp b/src/app/main.cpp
index bb10f99790a..f8ce9a87f44 100644
--- a/src/app/main.cpp
+++ b/src/app/main.cpp
@@ -299,6 +299,8 @@ int main(int argc, char **argv)
             && !qEnvironmentVariableIsSet("QT_DEVICE_PIXEL_RATIO")) {
         qputenv("QT_DEVICE_PIXEL_RATIO", "auto");
     }
+#else
+    qputenv("QT_AUTO_SCREEN_SCALE_FACTOR", "1");
 #endif // < Qt 5.6
 
     QLoggingCategory::setFilterRules(QLatin1String("qtc.*.debug=false"));