"machine_start_gcode":"M190 S[bed_temperature_initial_layer_single]\nM109 S[nozzle_temperature_initial_layer]\nPRINT_START EXTRUDER=[nozzle_temperature_initial_layer] BED=[bed_temperature_initial_layer_single]\n; You can use following code instead if your PRINT_START macro support Chamber and print area bedmesh\n; PRINT_START EXTRUDER=[nozzle_temperature_initial_layer] BED=[bed_temperature_initial_layer_single] Chamber=[chamber_temperature] PRINT_MIN={first_layer_print_min[0]},{first_layer_print_min[1]} PRINT_MAX={first_layer_print_max[0]},{first_layer_print_max[1]}",