Fem: Add suppressible extension to objects - fixes #12115

src/Mod/Fem/App/FemMeshObject.cpp

@@ -41,6 +41,8 @@ FemMeshObject::FemMeshObject()
     ADD_PROPERTY_TYPE(FemMesh, (), "FEM Mesh", Prop_NoRecompute, "FEM Mesh object");
     // in the regard of recomputes see:
     // https://forum.freecad.org/viewtopic.php?f=18&t=33329#p279203
+
+    suppressibleExt.initExtension(this);
 }
 
 FemMeshObject::~FemMeshObject() = default;