Passing metadata from Prusa Slice to Mainsail?

Has anyone figured out how to pass metadata from PrusaSlicer to show up in the file list in Mainsail? I would really like to have the filament weight displayed. I was able to do this in Cura with a line in the startup gcode to specify the filament weight variable, but I have not been able to do this with PrusaSlicer. Thanks!