diff --git a/src/slic3r/GUI/Gizmos/GLGizmosCommon.cpp b/src/slic3r/GUI/Gizmos/GLGizmosCommon.cpp
index 3ac1c39377..d26068ca24 100644
--- a/src/slic3r/GUI/Gizmos/GLGizmosCommon.cpp
+++ b/src/slic3r/GUI/Gizmos/GLGizmosCommon.cpp
@@ -73,8 +73,9 @@ Raycaster* CommonGizmosDataPool::raycaster() const
 ObjectClipper* CommonGizmosDataPool::object_clipper() const
 {
     ObjectClipper* oc = dynamic_cast<ObjectClipper*>(m_data.at(CommonGizmosDataID::ObjectClipper).get());
-    assert(oc);
-    return oc->is_valid() ? oc : nullptr;
+    // ObjectClipper is used from outside the gizmos to report current clipping plane.
+    // This function can be called when oc is nullptr.
+    return (oc && oc->is_valid()) ? oc : nullptr;
 }
 
 SupportsClipper* CommonGizmosDataPool::supports_clipper() const
diff --git a/src/slic3r/GUI/Gizmos/GLGizmosManager.cpp b/src/slic3r/GUI/Gizmos/GLGizmosManager.cpp
index ac7fe72e56..685e49d367 100644
--- a/src/slic3r/GUI/Gizmos/GLGizmosManager.cpp
+++ b/src/slic3r/GUI/Gizmos/GLGizmosManager.cpp
@@ -412,7 +412,8 @@ bool GLGizmosManager::gizmo_event(SLAGizmoEventType action, const Vec2d& mouse_p
 
 ClippingPlane GLGizmosManager::get_clipping_plane() const
 {
-    if (! m_common_gizmos_data->object_clipper()
+    if (! m_common_gizmos_data
+     || ! m_common_gizmos_data->object_clipper()
      || m_common_gizmos_data->object_clipper()->get_position() == 0.)
         return ClippingPlane::ClipsNothing();
     else {