Disconnect previous visual shader node connection before new connect

editor/plugins/visual_shader_editor_plugin.cpp

@@ -510,6 +510,17 @@ void VisualShaderEditor::_connection_request(const String &p_from, int p_from_in
 	}
 
 	undo_redo->create_action("Nodes Connected");
+
+	List<VisualShader::Connection> conns;
+	visual_shader->get_node_connections(type, &conns);
+
+	for (List<VisualShader::Connection>::Element *E = conns.front(); E; E = E->next()) {
+		if (E->get().to_node == to && E->get().to_port == p_to_index) {
+			undo_redo->add_do_method(visual_shader.ptr(), "disconnect_nodes", type, E->get().from_node, E->get().from_port, E->get().to_node, E->get().to_port);
+			undo_redo->add_undo_method(visual_shader.ptr(), "connect_nodes", type, E->get().from_node, E->get().from_port, E->get().to_node, E->get().to_port);
+		}
+	}
+
 	undo_redo->add_do_method(visual_shader.ptr(), "connect_nodes", type, from, p_from_index, to, p_to_index);
 	undo_redo->add_undo_method(visual_shader.ptr(), "disconnect_nodes", type, from, p_from_index, to, p_to_index);
 	undo_redo->add_do_method(this, "_update_graph");