Karabiner-elements: Can't rebind other keys to 'fn'

[Dalamar42]

Issue

I am trying to rebind left_control to fn and fn to left_command, but I am having the following issue:

• physical fn works correctly as left_command, but it also toggles the touch bar to show the F-keys as it did before my change
• physical left_control does not toggle the touch bar and seems to not do anything

I have seen a lot of issues where people lose the fn functionality when karabiner-elements is running, but I seem to be having the opposite problem in a way. I can't stop the physical fn key from behaving like fn or move the functionality to another key. I have also confirmed the same problem happens if I try to bind other keys to fn.

Versions

Laptop: Macbook Pro 15 (2016)
OSX: 10.12.5
Karabiner-Elements: 0.90.92

Event viewer results

Pressing physical fn:

eventType:FlagsChanged    code:0x37       name:left_command    flags:Cmd                                misc:characters:    
eventType:FlagsChanged    code:0x37       name:left_command    flags:                                   misc:characters:    

Pressing physical left_control:

eventType:FlagsChanged    code:0x3f       name:fn              flags:Fn                                 misc:characters:    
eventType:FlagsChanged    code:0x3f       name:fn              flags:                                   misc:characters:    

Config

{
    "global": {
        "check_for_updates_on_startup": true,
        "show_in_menu_bar": true,
        "show_profile_name_in_menu_bar": false
    },
    "profiles": [
        {
            "devices": [
                {
                    "disable_built_in_keyboard_if_exists": false,
                    "identifiers": {
                        "is_keyboard": true,
                        "is_pointing_device": false,
                        "product_id": 50475,
                        "vendor_id": 1133
                    },
                    "ignore": true
                },
                {
                    "disable_built_in_keyboard_if_exists": false,
                    "identifiers": {
                        "is_keyboard": true,
                        "is_pointing_device": false,
                        "product_id": 34304,
                        "vendor_id": 1452
                    },
                    "ignore": true
                }
            ],
            "fn_function_keys": {
                "f1": "display_brightness_decrement",
                "f10": "mute",
                "f11": "volume_decrement",
                "f12": "volume_increment",
                "f2": "display_brightness_increment",
                "f3": "mission_control",
                "f4": "launchpad",
                "f5": "illumination_decrement",
                "f6": "illumination_increment",
                "f7": "rewind",
                "f8": "play_or_pause",
                "f9": "fastforward"
            },
            "name": "Default profile",
            "selected": true,
            "simple_modifications": {
                "caps_lock": "escape",
                "fn": "left_command",
                "left_command": "left_control",
                "left_control": "fn"
            },
            "virtual_hid_keyboard": {
                "caps_lock_delay_milliseconds": 0,
                "keyboard_type": "ansi"
            }
        }
    ]
}

[jrus]

See #431, #543, and several other issues. (Try a search for fn or function or touchbar)

[Dalamar42]

I had a look at other issues before opening this one. There are a lot of people reporting touchbar issues, but I don't believe this particular issue has been reported before.

431 is about the media keys not working

543 is about the fn key not toggling the touchbar strip which others have reported as well. My issue is the opposite of that.

AFAIK there was a fix released to deal with issues like #543. The issue I'm experience could be a consequence of that fix.

[fastman]

I have the same issue - I'm unable to remap any key to act as fn key.
The same issue has been described in #576

Versions

Laptop: Macbook Pro 15 (2017)
OSX: 10.12.6
Karabiner-Elements: 0.91.13

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[alexhayes]

As of v11.6.0 this issue still stands.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[mneverov]

v12.0.0 still has this bug

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[alexhayes]

This looks to be resolved now in 12.1.0 🎉

I can map Fn to Control and Control to Fn and the touchbar works as expected (ie.. pressing Control changes the available "keys" on touchbar).

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[lmsmartins]

Same issue here. Not able to remap fn as left ctrl key. I'm able to remap left ctrl key as fn key though.
I'm using version 12.1.0.

[idchlife]

Using custom keyboard and fn key left from spacebar is discovered as 0xb0 without any name. Can't remap it to left option :(

edit: solved

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[yougotwill]

@idchlife How did you resolve the issue? When I press the Fn key nothing is reported in the EventViewer from my bluetooth keyboard.

[josh-collinsworth]

Having this issue on the latest version as well (12.4.0)

[idchlife]

@yougotwill @josh-collinsworth https://github.com/tekezo/Karabiner-Elements/issues/1617

Guys, try to start debug or something for key inputs, check your fn key and then edit needed files and build your own edition of Karabiner-Elements