standalone_keys_delay_milliseconds is not added to UI, because conflicts are bothering and might not be used very often.

fixed the case when continuous standalone keys are pressed

fixed default standalone key delay value

standalone keys delay milliseconds added to config and UI

Notes: to remove the outdated key in system user defaults, run defaults delete -g StandaloneKey

Example:

{
    "profiles": [
        {
            "name": "Default profile",
            "selected": true,
            "simple_modifications": {
                "caps_lock": "left_control"
            },
            "standalone_keys": {
                "caps_lock": "escape"
            },
            "one_to_many_mappings": {
                "left_control": ["left_control", "left_shift", "left_option", "left_command"]
            }
        }
    ]
}

One-to-many mappings

An attempt to add one-to-many mappings, example configuration:

{
    "one_to_many_mappings": {
        "left_control": ["left_control", "left_shift", "left_option", "left_command"]
    }
}

This is to get the hyper key.

Caveats

• Fn + xxx may not work as expected
• Multiple devices may not work as expected

Because I myself don't use either of them, if you have problems, I can try to fix

BREAKING CHANGE

The key in standalone_keys should be the original key on the keyboard, not the one got mapped in simple_modifications. For example, to map caps lock to control and escape, this

{
    "simple_modifications": {
        "caps_lock": "left_control"
    },
    "standalone_keys": {
        "left_control": "escape"
    }
}

should be changed to

{
    "simple_modifications": {
        "caps_lock": "left_control"
    },
    "standalone_keys": {
        "caps_lock": "escape"
    }
}