Karabiner - F19 (Capslock) to Control in Emacs

gistfile1.txt

{
    "description": "F19 (Capslock) to Control in Emacs",
    "manipulators": [
        {
            "conditions": [
                {
                    "bundle_identifiers": [
                        "^org\\.gnu\\.Emacs$"
                    ],
                    "type": "frontmost_application_if"
                }
            ],
            "from": {
                "key_code": "f19"
            },
            "to": [
                {
                    "key_code": "left_control"
                }
            ],
            "type": "basic"
        }
    ]
}