Startup error "Failed to configure AppDaemon Unknown field: appdaemon.plugins.HASS.hass.app_init_delay"

[aguscerdo]

What happened?

Updated appdaemon today and it doesn't start anymore. I am getting error Unknown field: appdaemon.plugins.HASS.hass.app_init_delay. I do not set this field in my AD yaml config.

I updated both appdaemon, which was only a version bump, and also updated HASS to 2026.2 at the same time.

Version

0.18.1

Installation type

Home Assistant add-on

Relevant log output

-----------------------------------------------------------
 App: AppDaemon
 Python Apps and Dashboard using AppDaemon 4.x for Home Assistant
-----------------------------------------------------------
 App version: 0.18.1
 You are running the latest version of this app.
 System: Home Assistant OS 17.0  (amd64 / qemux86-64)
 Home Assistant Core: 2026.2.1
 Home Assistant Supervisor: 2026.02.1
-----------------------------------------------------------
 Please, share the above information when looking for help
 or support in, e.g., GitHub, forums or the Discord chat.
-----------------------------------------------------------
s6-rc: info: service base-addon-banner successfully started
s6-rc: info: service fix-attrs: starting
s6-rc: info: service base-addon-log-level: starting
s6-rc: info: service fix-attrs successfully started
s6-rc: info: service base-addon-log-level successfully started
s6-rc: info: service legacy-cont-init: starting
s6-rc: info: service legacy-cont-init successfully started
s6-rc: info: service init-appdaemon: starting
s6-rc: info: service init-appdaemon successfully started
s6-rc: info: service appdaemon: starting
s6-rc: info: service appdaemon successfully started
s6-rc: info: service legacy-services: starting
[22:12:00] INFO: Starting AppDaemon...
s6-rc: info: service legacy-services successfully started
2026-02-09 22:12:03.020 ERROR AppDaemon: =====  Failed to configure AppDaemon  =====================================
2026-02-09 22:12:03.020 ERROR AppDaemon: Unknown field: appdaemon.plugins.HASS.hass.app_init_delay
2026-02-09 22:12:03.020 ERROR AppDaemon: ===========================================================================
[22:12:03] INFO: Service AppDaemon exited with code 1 (by signal 0)
s6-rc: info: service legacy-services: stopping
s6-rc: info: service legacy-services successfully stopped
s6-rc: info: service appdaemon: stopping
s6-rc: info: service appdaemon successfully stopped
s6-rc: info: service init-appdaemon: stopping
s6-rc: info: service init-appdaemon successfully stopped
s6-rc: info: service legacy-cont-init: stopping
s6-rc: info: service legacy-cont-init successfully stopped
s6-rc: info: service fix-attrs: stopping
s6-rc: info: service base-addon-log-level: stopping
s6-rc: info: service fix-attrs successfully stopped
s6-rc: info: service base-addon-log-level successfully stopped
s6-rc: info: service base-addon-banner: stopping
s6-rc: info: service base-addon-banner successfully stopped
s6-rc: warning: service s6rc-oneshot-runner is marked as essential, not stopping it
 Live

Relevant code in the app or config file that caused the issue

secrets: /homeassistant/secrets.yaml
appdaemon:
  time_zone: America/XYZ
  latitude: xyz
  longitude: xyz
  elevation: xyz
  app_dir: /homeassistant/appdaemon/apps/
  plugins:
    HASS:
      type: hass
      ha_url: https://abc.xyz.com
      token: XYZ
http:
  url: https://abc.xyz.com/
admin:
api:
hadashboard:

Anything else?

No response

[aguscerdo]

Ended up restoring a backup.
Version 0.17.13 works fine on both HASS 2026.1.3 and 2026.2.1.

Updating to version 0.18.1 caused the issue on both.