diff --git a/src/4.advanced_opengl/2.stencil_testing/stencil_testing.cpp b/src/4.advanced_opengl/2.stencil_testing/stencil_testing.cpp
index 15d5f9f..5cfd90e 100644
--- a/src/4.advanced_opengl/2.stencil_testing/stencil_testing.cpp
+++ b/src/4.advanced_opengl/2.stencil_testing/stencil_testing.cpp
@@ -255,6 +255,7 @@ int main()
         glDrawArrays(GL_TRIANGLES, 0, 36);
         glBindVertexArray(0);
         glStencilMask(0xFF);
+        glStencilFunc(GL_ALWAYS, 0, 0xFF);
         glEnable(GL_DEPTH_TEST);
 
         // glfw: swap buffers and poll IO events (keys pressed/released, mouse moved etc.)