diff --git a/Alpha_shapes_3/demo/Alpha_shapes_3/Viewer.cpp b/Alpha_shapes_3/demo/Alpha_shapes_3/Viewer.cpp
index e276df8661e..dd13883e3df 100644
--- a/Alpha_shapes_3/demo/Alpha_shapes_3/Viewer.cpp
+++ b/Alpha_shapes_3/demo/Alpha_shapes_3/Viewer.cpp
@@ -29,14 +29,14 @@ void Viewer::compile_shaders()
     //Vertex source code
     const char vertex_source[] =
     {
-         "#version 330 \n"
+         "#version 120 \n"
         "in highp vec4 vertex;\n"
         "in highp vec3 normal;\n"
 
         "uniform highp mat4 mvp_matrix;\n"
         "uniform highp mat4 mv_matrix; \n"
-        "out highp vec4 fP; \n"
-        "out highp vec3 fN; \n"
+        "varying highp vec4 fP; \n"
+        "varying highp vec3 fN; \n"
         "void main(void)\n"
         "{\n"
         "   fP = mv_matrix * vertex; \n"
@@ -47,7 +47,7 @@ void Viewer::compile_shaders()
     //Vertex source code
     const char fragment_source[] =
     {
-        "#version 330 \n"
+        "#version 120 \n"
         "in highp vec4 fP; \n"
         "in highp vec3 fN; \n"
         "uniform highp vec4 color; \n"
@@ -105,7 +105,7 @@ rendering_program.bind();
 //Vertex source code
 const char vertex_source_points[] =
 {
-     "#version 330 \n"
+     "#version 120 \n"
     "in highp vec4 vertex;\n"
 
     "uniform highp mat4 mvp_matrix;\n"
@@ -117,7 +117,7 @@ const char vertex_source_points[] =
 //Vertex source code
 const char fragment_source_points[] =
 {
-    "#version 330 \n"
+    "#version 120 \n"
     "uniform highp vec4 color; \n"
 
     "void main(void) { \n"
diff --git a/Alpha_shapes_3/demo/Alpha_shapes_3/Viewer.h b/Alpha_shapes_3/demo/Alpha_shapes_3/Viewer.h
index a5cc54aa490..5280aa622b3 100644
--- a/Alpha_shapes_3/demo/Alpha_shapes_3/Viewer.h
+++ b/Alpha_shapes_3/demo/Alpha_shapes_3/Viewer.h
@@ -3,13 +3,13 @@
 
 #include "typedefs.h"
 #include <QGLViewer/qglviewer.h>
-#include <QOpenGLFunctions_3_3_Core>
+#include <QOpenGLFunctions_2_1>
 #include <QOpenGLVertexArrayObject>
 #include <QOpenGLBuffer>
 #include <QOpenGLShaderProgram>
 
 
-class Viewer : public QGLViewer, protected QOpenGLFunctions_3_3_Core{
+class Viewer : public QGLViewer, protected QOpenGLFunctions_2_1{
   Q_OBJECT
 
   CGAL::Timer timer;
diff --git a/GraphicsView/include/CGAL/Qt/CreateOpenGLContext.h b/GraphicsView/include/CGAL/Qt/CreateOpenGLContext.h
index 514b6e8007e..7e321582f36 100644
--- a/GraphicsView/include/CGAL/Qt/CreateOpenGLContext.h
+++ b/GraphicsView/include/CGAL/Qt/CreateOpenGLContext.h
@@ -27,7 +27,7 @@ inline QGLContext* createOpenGLContext()
 {
     QOpenGLContext *context = new QOpenGLContext();
     QSurfaceFormat format;
-    format.setVersion(3,3);
+    format.setVersion(2,1);
     format.setProfile(QSurfaceFormat::CompatibilityProfile);
     context->setFormat(format);
     return QGLContext::fromOpenGLContext(context);