UndefinedError: 'None' has no attribute 'state' hanging up server

[Spirituss]

Checklist

• I'm running the latest version of CustomUI (Update guide) or using a specific release that is not marked as "Broken".
• I tried to force-refresh (Ctrl+Shift+R / Ctrl+F5) the browser
• (Optional, but recommended) I'm using Chrome or tried to reproduce the feature on Chrome.

Browser + Version:
Opera 63.0.3368.35 / Chrome Version 74.0.3729.157 (Official Build) (64-bit)

CustomUI version:
20190518

Home Assistant release (hass --version):
Raspberry PI / Doker / HASS.io 0.97.2

Problem-relevant configuration.yaml entries:

Unknown.

I receive tons of errors in HA log as below. It's not clear how to find the HA element, that cause this error. The main problem is that the errors arise too often (several per second), thus not only HA, but even Raspberry hangs up after some hours of error log increase.

Problem-relevant Home Assistant log entries:

ERROR (MainThread) [homeassistant.helpers.service] Error rendering data template: UndefinedError: 'None' has no attribute 'state'

Any errors from browser Javascript console:

[Spirituss]

Still waiting for problem fix. It overload the log file of HA. Current version - 0.102.1