diff --git a/src/gui/kernel/qsurfaceformat.cpp b/src/gui/kernel/qsurfaceformat.cpp
index d078336d733..18fde5716b1 100644
--- a/src/gui/kernel/qsurfaceformat.cpp
+++ b/src/gui/kernel/qsurfaceformat.cpp
@@ -35,6 +35,7 @@
 
 #include <QtCore/qatomic.h>
 #include <QtCore/QDebug>
+#include <QOpenGLContext>
 
 #ifdef major
 #undef major
@@ -758,6 +759,11 @@ Q_GLOBAL_STATIC(QSurfaceFormat, qt_default_surface_format)
  */
 void QSurfaceFormat::setDefaultFormat(const QSurfaceFormat &format)
 {
+    QOpenGLContext *globalContext = QOpenGLContext::globalShareContext();
+    if (globalContext && globalContext->isValid()) {
+        qWarning("Warning: Setting a new default format with a different version or profile after "
+                 "the global shared context is created may cause issues with context sharing.");
+    }
     *qt_default_surface_format() = format;
 }