Hi Eddy,
Well, thanks for that. I will try it as a controlled experiment.
However, I delete all cookies from my browser(s) several times a day and so this may not be a workable solution. In any case, the Avast software is installed on my machine and so surely it should store such settings in the System folder, or wherever all other installed software programs store their particular settings.
Saving these details in cookies does not seem to be a sensible approach. A sceptic might come to the conclusion that Avast is keen to ensure that the default low-privacy settings remain and do not get changed by the user!