How to use apple global/language key as an outgoing modifier in complex modification

[popbones]

I’m trying to setup shortcuts to some new macOS window management shortcuts which heavily involves the global key found on modern Mac keyboards. I think in Karabiner, the key code is:

{
  "apple_vendor_keyboard_key_code": "language"
}

For example, to arrange window as left half of the screen, the default keyboard shortcut is ctrl + language + left_arrow.

I have been successful in mapping the “application” key on my full size PC keyboard to the language key by itself via simple modification. It works just fine as in I have no trouble to trigger the key combo.

However, I’m trying to map the same key to a DualShock 4 controller and I need to use complex modification because I want to use one button to cycle through a list of layouts.

The problem however is that I couldn’t figure out how to use the language key as a modifier.

For sake of the discussion, let’s say I want to a Complex Modification Manipulator to emit ctrl + language + f which is the macOS 15 shortcut to make a window “fill the screen”.

[tekezo]

The globe key (fn key) handling has issue, and it is solved in the latest beta version. https://github.com/pqrs-org/Karabiner-Elements/issues/3879#issuecomment-2381071748

You can use "modifiers": ["fn"] or "key_code": "fn" to use the globe key. For example, the following json changes shift+f11 to control+fn+left arrow.

        {
            "from": {
                "key_code": "f11",
                "modifiers": {
                    "mandatory": ["left_shift"],
                    "optional": ["any"]
                }
            },
            "to": [
                {
                    "key_code": "left_arrow",
                    "modifiers": ["fn", "left_control"]
                }
            ],
            "type": "basic"
        }

[popbones]

Thank you for the quick reply.

I'll try that tomorrow and update the issue afterwords.

On a side note, is the language key always the same as fn key?

To clarify my question. What I mean is the following:

1. If an Apple keyboard has an fn key but not a global key, does it use the same key code as the language key?

2. If an Apple keyboard has a language key with the global icon but not an fn key. (A bit of a stretch, but I think the iPad Magic Keyboard thing is like that). Are they the same key in this case?

3. What about PC keyboards? Do they use the same key code?

Thanks.

[tekezo]

• The fn key and the globe key are exactly the same.
• In Karabiner-Elements, it is treated as the fn key, so you can use it by remapping a key to the fn key on a PC keyboard.
• Some PC keyboards have an fn key, but it is not compatible with macOS's fn key (global key). Additionally, the PC fn key's function is often handled entirely within the keyboard hardware, meaning it doesn't send key events, so the likelihood of it being usable is quite low. Instead, you will need to remap another key, like the right shift key, to the fn key using Karabiner-Elements.

[popbones]

@tekezo Thank you very much.

I've confirmed v15.0.17 works fine for me. Closing the issue.