slicer param print min & max cannot be passed to klipper

[coolouba]

thanks for your awesome work!
i follow every step in the readme doc
but klipper did not get the param in prusaslicer start gcode
msg in fluidd console is:

// Unknown command:"PRINT_MIN=56.0803,51.7303"

// Unknown command:"PRINT_MAX=198.92,128.27"

any help will be appreciate，thx

1.code in slicer（prusa slicer 2.5.0） start code zone:
PRINT_MIN={first_layer_print_min[0]},{first_layer_print_min[1]}
PRINT_MAX={first_layer_print_max[0]},{first_layer_print_max[1]}
PRINT_START
2.code in printer.cfg
[gcode_macro PRINT_START]
gcode:
G92 E0
SET_GCODE_OFFSET Z=0
G28
CLEAN_NOZZLE
BED_MESH_CLEAR
STATUS_HOMING
G28
STATUS_CLEANING
CLEAN_NOZZLE
G28 Z0
STATUS_MESHING
BED_MESH_CALIBRATE PRINT_MIN={params.PRINT_MIN} PRINT_MAX={params.PRINT_MAX} FORCE_NEW_MESH=True
STATUS_CALIBRATING_Z
CALIBRATE_Z
G28 X0
G28 Y0
STATUS_BUSY
M117 Printing