I don't know if the fact that I don't have the avast store as an option in the avastUI (I unchecked that option a long time ago), so I don't if that might have an impact in not being able to open the shopping cart. Though that said, I have clicked some other options/offers to capture images and that worked taking me to a cart of sorts within the UI.
Currently I have silent/gaming mode enabled, so I'm not getting any popups or offers, etc.