diff --git a/Boolean_set_operations_2/demo/Boolean_set_operations_2_GraphicsView/boolean_operations_2.qrc b/Boolean_set_operations_2/demo/Boolean_set_operations_2_GraphicsView/boolean_operations_2.qrc
index 99dbf085a82..fb351f4bfb5 100644
--- a/Boolean_set_operations_2/demo/Boolean_set_operations_2_GraphicsView/boolean_operations_2.qrc
+++ b/Boolean_set_operations_2/demo/Boolean_set_operations_2_GraphicsView/boolean_operations_2.qrc
@@ -59,7 +59,7 @@
   <qresource prefix="/cgal/Actions" >
     <file>icons/union.xpm</file>
   </qresource>
-  <qresource prefix="/cgal" lang="en" >
+  <qresource prefix="/cgal" >
     <file>help/index.html</file>
   </qresource>
   <qresource prefix="/cgal/Input" >
diff --git a/GraphicsView/demo/Bounding_volumes/Bounding_volumes.qrc b/GraphicsView/demo/Bounding_volumes/Bounding_volumes.qrc
index e6fab9d1307..ee9a847d7be 100644
--- a/GraphicsView/demo/Bounding_volumes/Bounding_volumes.qrc
+++ b/GraphicsView/demo/Bounding_volumes/Bounding_volumes.qrc
@@ -2,7 +2,7 @@
   <qresource prefix="/cgal/Actions" >
     <file>icons/min_circle.png</file>
   </qresource>
-  <qresource prefix="/cgal/help" lang="en" >
+  <qresource prefix="/cgal/help" >
     <file alias="about_CGAL.html" >../resources/about_CGAL.html</file>
     <file>about_Bounding_volumes.html</file>
   </qresource>
diff --git a/GraphicsView/demo/Circular_kernel_2/Circular_kernel_2.qrc b/GraphicsView/demo/Circular_kernel_2/Circular_kernel_2.qrc
index 300eb1884ab..c96356cfa55 100644
--- a/GraphicsView/demo/Circular_kernel_2/Circular_kernel_2.qrc
+++ b/GraphicsView/demo/Circular_kernel_2/Circular_kernel_2.qrc
@@ -1,5 +1,5 @@
 <RCC>
-  <qresource prefix="/cgal/help" lang="en" >
+  <qresource prefix="/cgal/help" >
     <file>about_Circular_kernel_2.html</file>
   </qresource>
 </RCC>
diff --git a/GraphicsView/demo/Generator/Generator_2.qrc b/GraphicsView/demo/Generator/Generator_2.qrc
index 80f34477ca7..6e512c4ef3c 100644
--- a/GraphicsView/demo/Generator/Generator_2.qrc
+++ b/GraphicsView/demo/Generator/Generator_2.qrc
@@ -1,5 +1,5 @@
 <RCC>
-  <qresource prefix="/cgal/help" lang="en" >
+  <qresource prefix="/cgal/help" >
     <file alias="about_CGAL.html" >../resources/about_CGAL.html</file>
     <file>about_Generator_2.html</file>
   </qresource>
diff --git a/GraphicsView/demo/Polygon/Polygon_2.qrc b/GraphicsView/demo/Polygon/Polygon_2.qrc
index 3c7cf38ab82..da128816fce 100644
--- a/GraphicsView/demo/Polygon/Polygon_2.qrc
+++ b/GraphicsView/demo/Polygon/Polygon_2.qrc
@@ -1,5 +1,5 @@
 <RCC>
-  <qresource prefix="/cgal/help" lang="en" >
+  <qresource prefix="/cgal/help" >
     <file alias="about_CGAL.html" >../resources/about_CGAL.html</file>
     <file>about_Polygon_2.html</file>
   </qresource>
diff --git a/GraphicsView/demo/Segment_Delaunay_graph_2/Segment_voronoi_2.qrc b/GraphicsView/demo/Segment_Delaunay_graph_2/Segment_voronoi_2.qrc
index 906398eb20e..70d1287e717 100644
--- a/GraphicsView/demo/Segment_Delaunay_graph_2/Segment_voronoi_2.qrc
+++ b/GraphicsView/demo/Segment_Delaunay_graph_2/Segment_voronoi_2.qrc
@@ -3,7 +3,7 @@
     <file>icons/constrained_triangulation_show_constraints.png</file>
     <file>icons/constrained_triangulation.png</file>
   </qresource>
-  <qresource prefix="/cgal/help" lang="en" >
+  <qresource prefix="/cgal/help" >
     <file alias="about_CGAL.html" >../resources/about_CGAL.html</file>
     <file>about_Segment_voronoi_2.html</file>
   </qresource>
diff --git a/GraphicsView/demo/Triangulation_2/Constrained_Delaunay_triangulation_2.qrc b/GraphicsView/demo/Triangulation_2/Constrained_Delaunay_triangulation_2.qrc
index 3c0165f38be..e77fb183013 100644
--- a/GraphicsView/demo/Triangulation_2/Constrained_Delaunay_triangulation_2.qrc
+++ b/GraphicsView/demo/Triangulation_2/Constrained_Delaunay_triangulation_2.qrc
@@ -5,7 +5,7 @@
     <file>icons/constrained_triangulation_show_constraints.png</file>
     <file>icons/constrained_triangulation.png</file>
   </qresource>
-  <qresource prefix="/cgal/help" lang="en" >
+  <qresource prefix="/cgal/help" >
     <file alias="about_CGAL.html" >../resources/about_CGAL.html</file>
     <file>about_Constrained_Delaunay_triangulation_2.html</file>
   </qresource>
diff --git a/GraphicsView/demo/Triangulation_2/Delaunay_triangulation_2.qrc b/GraphicsView/demo/Triangulation_2/Delaunay_triangulation_2.qrc
index d24eba6673f..b1fa77544ef 100644
--- a/GraphicsView/demo/Triangulation_2/Delaunay_triangulation_2.qrc
+++ b/GraphicsView/demo/Triangulation_2/Delaunay_triangulation_2.qrc
@@ -5,7 +5,7 @@
     <file>icons/triangulation.png</file>
     <file>icons/circumcenter.png</file>
   </qresource>
-  <qresource prefix="/cgal/help" lang="en" >
+  <qresource prefix="/cgal/help" >
     <file alias="about_CGAL.html" >../resources/about_CGAL.html</file>
     <file>about_Delaunay_triangulation_2.html</file>
   </qresource>
diff --git a/GraphicsView/demo/Triangulation_2/Regular_triangulation_2.qrc b/GraphicsView/demo/Triangulation_2/Regular_triangulation_2.qrc
index dee0e4e6c35..161792e78ca 100644
--- a/GraphicsView/demo/Triangulation_2/Regular_triangulation_2.qrc
+++ b/GraphicsView/demo/Triangulation_2/Regular_triangulation_2.qrc
@@ -1,6 +1,6 @@
 <RCC>
   <qresource prefix="/cgal/Actions" />
-  <qresource prefix="/cgal/help" lang="en" >
+  <qresource prefix="/cgal/help" >
     <file alias="about_CGAL.html" >../resources/about_CGAL.html</file>
     <file>about_Regular_triangulation_2.html</file>
   </qresource>
diff --git a/GraphicsView/demo/resources/CGAL.qrc b/GraphicsView/demo/resources/CGAL.qrc
index 456ba1d3617..47b2c5eec03 100644
--- a/GraphicsView/demo/resources/CGAL.qrc
+++ b/GraphicsView/demo/resources/CGAL.qrc
@@ -1,5 +1,5 @@
 <RCC>
-  <qresource prefix="/cgal/help" lang="en" >
+  <qresource prefix="/cgal/help" >
     <file>about_CGAL.html</file>
   </qresource>
   <qresource prefix="/cgal/logos">