The extended gcode is now only supported by Prusa (https://github.com/prusa3d/PrusaSlicer/issues/3114) A pull request https://github.com/MarlinFirmware/Marlin/pull/15739 aims to extend the gcode in upstream Marlin as well
The extended gcode is now only supported by Prusa (https://github.com/prusa3d/PrusaSlicer/issues/3114) A pull request https://github.com/MarlinFirmware/Marlin/pull/15739 aims to extend the gcode in upstream Marlin as well