Karabiner Elements hyper key with escape

karabiner.json

"complex_modifications": {
                "rules": [
                    {
                        "manipulators": [
                            {
                                "description": "Change caps_lock to command+control+option+shift. Escape if no other key used.",
                                "from": {
                                    "key_code": "caps_lock",
                                    "modifiers": {
                                        "optional": [
                                            "any"
                                        ]
                                    }
                                },
                                "to": [
                                    {
                                        "key_code": "left_shift",
                                        "modifiers": [
                                            "left_command",
                                            "left_control",
                                            "left_option"
                                        ]
                                    }
                                ],
                                "to_if_alone": [
                                    {
                                        "key_code": "escape",
                                        "modifiers": {
                                            "optional": [
                                                "any"
                                            ]
                                        }
                                    }
                                ],
                                "type": "basic"
                            }
                        ]
                    }
                ]
            },

When I try this I get the following Log error from Karabiner-Elements (v):

[2019-04-03 20:51:08.064] [error] [grabber] karabiner.json error: to_if_alone entry error: modifiers error: json must be array or string, but is {"optional":["any"]}

This appears to be a recent regression (probably in 12.3.0). I have complex modifications like this that stopped working after upgrading. Removing the modifiers entry is not sufficient, because it will stop recognizing the defined keycode if any other modifier is pressed.

I just ran into this after updating Karabiner-Elements to 12.3.0

I found that deleting the "modifiers" property from the "from" and "to_if_alone" directives solved the problem.

            "complex_modifications": {
                "rules": [
                    {
                        "manipulators": [
                            {
                                "description": "Change caps_lock to command+control+option+shift.",
                                "from": {
                                    "key_code": "caps_lock"
                                },
                                "to": [
                                    {
                                        "key_code": "left_shift",
                                        "modifiers": [
                                            "left_command",
                                            "left_control",
                                            "left_option"
                                        ]
                                    }
                                ],
                                "to_if_alone": [
                                    {
                                        "key_code": "escape"
                                    }
                                ],
                                "type": "basic"
                            }
                        ]
                    }
                ]
            }

@bgooseman´s solution worked for me. Thanks!

@bgooseman Thanks for your solution

Thank you! That helped!