https://support.avast.com/en-in/article/Antivirus-CyberCapture
Thank you for the link, I will re-install and try with this disabled.
You're welcome. 
Ok, so far all is good with CyberCapture disabled, also seems to have solved the problem reported with the previous release.
Thanks again.
Ok, so I have an observation with latest beta release, similar to my post re v19.8.2393 (
https://forum.avast.com/index.php?topic=229461.msg1522692#msg1522692).
This again relates to the SierraChart software, which has two chart rendering modes Windows GDI & OpenGL. If I enable OpenGL rendering, then 'Avast Behaviour Shield' is often seen to fully occupy 1 core/thread, which in turn leads to a much less responsive user interface.
Strangely, this still happens (although to a lesser extent) when Behaviour Shield is disabled. In addition to this, I have set exceptions for SierraChart software and associated data files, but this does not stop the interference of Behaviour Shield.
I do not see any evidence of the behaviour when using Windows GDI rendering, nor did I experience this behaviour when Avast was fully uninstalled.
Avast Premium Security ver 19.9.2394 (build 19.9.4824.537)
Windows 10 Pro v1903 build 18362.418