Unable to map some consumer_key_code: "ac_back", "ac_forward"

[joonhyuk]

type:down            HID usage: 12,548    name:{"consumer_key_code":"ac_back"}                         misc:
type:up              HID usage: 12,548    name:{"consumer_key_code":"ac_back"}                         misc:
type:down            HID usage: 12,549    name:{"consumer_key_code":"ac_forward"}                      misc:
type:up              HID usage: 12,549    name:{"consumer_key_code":"ac_forward"}                      misc:

I wanna remap "ac_back", "ac_forward" to browser back/forward.
Those are from thinkpad keyboard (more precisely, "TEX Shinobi")

Karabiner Eventviewer could recognize them but simple mapping not worked.
Of course, complex modification with them also unavailable.

(Seems to be known issue)

[Muirium]

Here's one of my rules using a "consumer_key_code" class of key. I found you have to spell out the "consumer_key_code" for yourself, then it seems to work just fine.

  "description": "⚙️ Preferences: ⌥ Option + ⏩ ⇨ Software Update Preferences Pane",
  "manipulators": [
    {
      "type": "basic",
      "from": {
        "consumer_key_code": "fast_forward",
        "modifiers": {
          "mandatory": [
            "option"
          ],
          "optional": [
            "caps_lock"
          ]
        }
      },
      "to": [
        {
          "shell_command": "open /System/Library/PreferencePanes/SoftwareUpdate.prefPane"
        }
      ]
    }
  ]
}

[akak0000]

This rule isn't working for me:

 {
                      "description": "Y to undo 2",
                      "manipulators": [
                        {
                          "from": {
                            "consumer_key_code": "al_terminal_lock_or_screensaver"
                          },
                          "to": [
                            {
                              "key_code": "z",
                              "modifiers": [
                                "left_command"
                              ]
                            }
                          ],
                          "type": "basic"
                        }
                      ]
                    }

Any ideas why? I'm using Event Viewer to make sure that that is the correct key firing which it is

[akak0000]

[robertrosman]

Just came here to say that consumer_key_code works great for me too, so you can use this config to map ac_back and ac_forward to Google chrome back/forward:

{
    "description": "Navigation keys (ac_back and ac_forward)",
    "manipulators": [
        {
            "from": {
                "consumer_key_code": "ac_back",
                "modifiers": {
                    "optional": [
                        "any"
                    ]
                }
            },
            "to": [
                {
                    "key_code": "8",
                    "modifiers": [
                        "left_command",
                        "right_option"
                    ]
                }
            ],
            "type": "basic"
        },
        {
            "from": {
                "consumer_key_code": "ac_forward",
                "modifiers": {
                    "optional": [
                        "any"
                    ]
                }
            },
            "to": [
                {
                    "key_code": "9",
                    "modifiers": [
                        "left_command",
                        "right_option"
                    ]
                }
            ],
            "type": "basic"
        }
    ]
}