Weird UTF-8 conversion problem (accessing logbook and history)

Hi all,

I am using HA 0.84.3 on a Raspberry Pi with 120 GB SSD.

The following components are currently loaded:

  • apcupsd
  • api
  • auth
  • automation
  • binary_sensor
  • binary_sensor.xiaomi_aqara
  • camera
  • camera.mjpeg
  • camera.onvif
  • cloud
  • config
  • config.auth
  • config.auth_provider_homeassistant
  • config.automation
  • config.config_entries
  • config.core
  • config.customize
  • config.device_registry
  • config.entity_registry
  • config.group
  • config.script
  • conversation
  • cover
  • cover.xiaomi_aqara
  • device_tracker
  • dialogflow
  • discovery
  • ffmpeg
  • frontend
  • group
  • history
  • http
  • introduction
  • light
  • light.xiaomi_aqara
  • light.yeelight
  • lock
  • lock.xiaomi_aqara
  • logbook
  • lovelace
  • map
  • notify
  • notify.html5
  • onboarding
  • owntracks
  • panel_iframe
  • recorder
  • script
  • sensor
  • sensor.apcupsd
  • sensor.moon
  • sensor.template
  • sensor.time_date
  • sensor.xiaomi_aqara
  • sensor.yr
  • sun
  • switch
  • switch.xiaomi_aqara
  • system_log
  • tts
  • updater
  • webhook
  • websocket_api
  • xiaomi_aqara
  • zone

Frontend JavaScript version is “latest”

I get the error
2018-12-18 20:14:56 ERROR (MainThread) [frontend.js.latest.201812111] http://10.0.100.201:8123/frontend_latest/app-19cc9e53.js:2169:21083 Uncaught SyntaxError: Expected “date”, “number”, “plural”, “select”, “selectordinal” or “time” but “\xE7” found
when accessing logbook and history links at the frontend.

The recorder component is in use, the events are properly recorded in the SQLite3 db file, I have enough diskspace (whol a lot)

Obviously “\xE7” stands for small caps latin letter c with cedilla (ç)

I’m using Turkish names for some of my automations and as far as I checked my database for events, the UTF-8 names are really converted to hexadecimal codes.

I checked out which programming component causes this and I found out that it is polymer.

As I haven’t enough time, I didn’t try making any changes in the code.

Can anyone provide a solution for this matter?