Button Type in Entities Card Broken in UI Editor

Hi, I have a Entities card that I’ve been able to edit in YAML, until now. Just updated to 2021.7.0. When trying to edit it, I get lots of errors and I can’t save changes. Here is the card’s YAML.

type: entities
show_header_toggle: false
state_color: true
title: Siren / Chime
entities:
  - type: button
    action_name: Toggle Siren
    icon: mdi:volume-high
    name: Alarm Siren
    tap_action:
      action: call-service
      confirmation:
        text: Toggle Alarm Siren?
      service: switch.toggle
      service_data:
        entity_id: switch.zooz_zse19_siren_switch
  - type: divider
  - entity: sensor.zooz_zse19_siren_temperature
    name: Temperature
  - entity: sensor.zooz_zse19_siren_relative_humidity
    name: Humidity
  - entity: sensor.zooz_zse19_siren_battery_level
    name: Battery Level (0721)
  - entity: zwave.zooz_zse19_siren
    name: Zooz ZSE19 Siren

Here are the errors:

Configuration errors detected:

    Required key "entities.0.entity" is missing.
    Required key "entities.0.view" is missing.
    Required key "entities.0.view" is missing.
    Required key "entities.0.view" is missing.
    Required key "entities.0.conditions" is missing.
    Required key "entities.0.url" is missing.
    Required key "entities.0.entities" is missing.
    Required key "entities.0.entity" is missing.
    Required key "entities.0.attribute" is missing.
    Required key "entities.0.service" is missing.
    Required key "entities.0.text" is missing.

Visual editor is not supported for this configuration:

    Key "entities.0.type" is not expected or not supported by the visual editor.
    Key "entities.0.action_name" is not expected or not supported by the visual editor.
    The provided value for "entities.0" is not supported by the visual editor. We support (string) but received ({"type":"button","action_name":"Toggle Siren","icon":"mdi:volume-high","name":"Alarm Siren","tap_action":{"action":"call-service","confirmation":{"text":"Toggle Alarm Siren?"},"service":"switch.toggle","service_data":{"entity_id":"switch.zooz_zse19_siren_switch"}}}).
    Key "entities.0.icon" is not expected or not supported by the visual editor.
    The provided value for "entities.0.type" is not supported by the visual editor. We support (literal) but received ("button").
    Key "entities.0.action_name" is not expected or not supported by the visual editor.
    Key "entities.0.tap_action" is not expected or not supported by the visual editor.
    The provided value for "entities.0.type" is not supported by the visual editor. We support (literal) but received ("button").
    Key "entities.0.action_name" is not expected or not supported by the visual editor.
    Key "entities.0.icon" is not expected or not supported by the visual editor.
    Key "entities.0.name" is not expected or not supported by the visual editor.
    Key "entities.0.tap_action" is not expected or not supported by the visual editor.
    The provided value for "entities.0.type" is not supported by the visual editor. We support (literal) but received ("button").
    Key "entities.0.action_name" is not expected or not supported by the visual editor.
    Key "entities.0.icon" is not expected or not supported by the visual editor.
    Key "entities.0.name" is not expected or not supported by the visual editor.
    Key "entities.0.tap_action" is not expected or not supported by the visual editor.
    The provided value for "entities.0.type" is not supported by the visual editor. We support (literal) but received ("button").
    Key "entities.0.action_name" is not expected or not supported by the visual editor.
    Key "entities.0.icon" is not expected or not supported by the visual editor.
    Key "entities.0.name" is not expected or not supported by the visual editor.
    Key "entities.0.tap_action" is not expected or not supported by the visual editor.
    The provided value for "entities.0.type" is not supported by the visual editor. We support (literal) but received ("button").
    Key "entities.0.action_name" is not expected or not supported by the visual editor.
    Key "entities.0.tap_action" is not expected or not supported by the visual editor.
    The provided value for "entities.0.type" is not supported by the visual editor. We support (literal) but received ("button").
    Key "entities.0.action_name" is not expected or not supported by the visual editor.
    Key "entities.0.icon" is not expected or not supported by the visual editor.
    Key "entities.0.name" is not expected or not supported by the visual editor.
    Key "entities.0.tap_action" is not expected or not supported by the visual editor.
    The provided value for "entities.0.type" is not supported by the visual editor. We support (literal) but received ("button").
    Key "entities.0.action_name" is not expected or not supported by the visual editor.
    Key "entities.0.icon" is not expected or not supported by the visual editor.
    Key "entities.0.tap_action" is not expected or not supported by the visual editor.
    The provided value for "entities.0.type" is not supported by the visual editor. We support (literal) but received ("button").
    Key "entities.0.tap_action" is not expected or not supported by the visual editor.
    The provided value for "entities.0.type" is not supported by the visual editor. We support (literal) but received ("button").
    Key "entities.0.action_name" is not expected or not supported by the visual editor.
    Key "entities.0.tap_action" is not expected or not supported by the visual editor.
    The provided value for "entities.0.type" is not supported by the visual editor. We support (custom element type) but received ("button").

You can still edit your config in YAML. 

I’ve been looking at the docs to see if something has changed, but haven’t found anything. If you notice something in the source that has changed, please let me know. TIA!

Also, I moved some stuff around, deleted some stuff, and it seems like it doesn’t like the button code. I did, at one point, get things pasted such that it let me save it, the only difference being the bottom four lines moved to the top. But coming right back into it again, showed the same errors. The card image is blurred, with the wait circle icon, and the Save button is not available. This is some flaky behavior. I tried clearing the browser cache, but that doesn’t seem to help. Just happened again, moved the top four lines back to bottom, errors disappeared, saved it. Went right back into edit and the errors showed again. Appears to be a BUG. Note that the card actually works. The UI YAML editor/parser seems to be broken.