Karabiner-Elements Magic Keyboard mappings

karabiner.json

{
    "rules": [
        {
            "description": "Eject to Screenshot",
            "manipulators": [
                {
                    "from": {
                        "consumer_key_code": "eject"
                    },
                    "to": [
                        {
                            "key_code": "4",
                            "modifiers": [
                                "left_command",
                                "left_shift"
                            ]
                        }
                    ],
                    "type": "basic"
                },
                {
                    "from": {
                        "consumer_key_code": "eject",
                        "modifiers": {
                            "mandatory": [
                                "fn"
                            ]
                        }
                    },
                    "to": {
                        "key_code": "q",
                        "modifiers": [
                            "left_control",
                            "left_command"
                        ]
                    },
                    "type": "basic"
                }
            ]
        }
    ]
}