Also this post in avast forum
Avast Community.
Hello Andrea,
Thank you for contacting AVG support community.
Sorry for the trouble caused.
Could you please confirm on how long you are facing this issue?
Thank you and keep us updated.
Thank you for writing back to us, Andrea.
To further look into this & help you, we've sent you an email with detailed instructions to contact our additional support.
Please check your inbox/spam folders to find the email and use it to contact them at your convenient time.
Issue appeared right after I updated avg to 22.8.3250 version. It's just as though browser threat scanning in smart scan has disappear, and repairing doesn't change anything. I'm not sure if it's a bug, or a feature of the new release.