Cura/resources/definitions/custom.def.json

{
    "id": "custom",
    "version": 2,
    "name": "Custom FDM printer",
    "inherits": "fdmprinter",
    "metadata": {
        "visible": true,
        "author": "Ultimaker",
        "manufacturer": "Custom",
        "category": "Custom",
        "file_formats": "text/x-gcode",
        "has_materials": true,
        "preferred_material": "*pla*",
        "first_start_actions": ["MachineSettingsAction"]
    }
}