diff --git a/src/slic3r/GUI/GLCanvas3D.cpp b/src/slic3r/GUI/GLCanvas3D.cpp index f18b1e71c..3fc090c6b 100644 --- a/src/slic3r/GUI/GLCanvas3D.cpp +++ b/src/slic3r/GUI/GLCanvas3D.cpp @@ -1383,7 +1383,7 @@ bool GLCanvas3D::Selection::is_single_full_instance() const return false; int object_idx = m_valid ? get_object_idx() : -1; - if (object_idx == -1) + if ((object_idx < 0) || ((int)m_model->objects.size() < object_idx)) return false; int instance_idx = (*m_volumes)[*m_list.begin()]->instance_idx();