Janusz Łaski

Something like this?

https://www.aliexpress.com/item/1857358266.html

google overscan

or try this:

https://www.maketecheasier.com/fix-overscan-on-tv/

Google Assistant is available only in few supported countries. 

In my case (Poland), setting the menu language and LG Services to English (UK) did the job.

@td47 Thank you for hints. I am on newest firmware issued for OLED65C9PLA i.e. 05.00.10 (sorry for typo in OP). I know that there is plenty of options to cast video from my PC.  Here, I am trying to figure out whether my TV's behavior is common or rather I have something messed with my BeOS settings or something.

48 minutes ago, td47 said:

@Janusz Łaski Ensure that your Windows 10 device is at least at OS version 20H1, or better still 20H2. They have improved the casting/projecting software, to make it more reliable.

Thanks for reply. Actually, I'm on 20H2. I am convinced, it is LG WebOS (version 05.00.01) related as I have this issue on few laptops including one with the newest insider win10 version (21XX).

Is it work for you as it should? What is your firmware version?

I was trying to connect My LG TV as a wireless display, just as on this video:

Unfortunately it works only first time until disconnecting. To reconnect I need to restart TV, sometimes a few times. Sometimes TV is not detectable at all. How it works for you?

PC or laptop connected via HDMI works perfect for me. HD main content on LGTV (as extended desktop, not mirror) and stats or onboards (as many windows I need) on first (PC) monitor.