fixed crash problem with undefined twoDimCanvases + more
fixed crash problem with undefined twoDimCanvases + more

IPS-LMU/EMU-webApp,IPS-LMU/EMU-webApp,IPS-LMU/EMU-webApp,IPS-LMU/EMU-webApp,IPS-LMU/EMU-webApp,IPS-LMU/EMU-webApp