Automations stopped working with 0.50dev

Configuration
1

With 0.50dev my automations stopped working due to the following error:

ERROR (MainThread) [homeassistant.config] Invalid config for [automation]: extra keys not allowed @ data['condition'][0]['conditions'][0]['to']. Got None not a valid value for dictionary value @ data['condition'][0]['conditions'][0]['condition']. Got None.

Unfortunately the reference to the broken config-line is not helpful because it leads to the line:
automation: !include automations.yaml

But regarding the error I’m assuming the following snippet being the error:

alias: "Lichter vergessen"
  trigger:
    platform: state
    entity_id: group.familie
    to: 'not_home'
    for:
      hours: 0
      minutes: 15
      seconds: 0
  condition:
    condition: or
    conditions:
      - condition: state
        entity_id: light.wohnzimmer_licht
        to: 'on'
      - condition: state
        entity_id: light.speisesaal_licht
        to: 'on'
      - condition: state
        entity_id: light.bad_licht
        to: 'on'
      - condition: state
        entity_id: light.romy_licht
        to: 'on'
  action:
    - service: notify.telegram_haushalt
      data:
        message: 'Lichter sind noch an!'
        data:
          keyboard:
            - '/ausmachen'

Another thought: From 0.50 on the condition/trigger “state: on” is obsolete and has to be replaced with “to: on”. Maybe this went wrong in my config?

2

For condition it has to be “state: on”