Use the global stack instance variable and account for it potentially being None
Use the global stack instance variable and account for it potentially being None

hmflash/Cura,totalretribution/Cura,fieldOfView/Cura,fieldOfView/Cura,senttech/Cura,Curahelper/Cura,senttech/Cura,ynotstartups/Wanhao,Curahelper/Cura,totalretribution/Cura,ynotstartups/Wanhao,hmflash/Cura