Can't use Firefox for any site with a shopping cart.
For several days, on all sites I have visited with shopping carts, a low-opacity grey rectangle appears in the upper right hand corner of the screen. Nothing appearing on… (read more)
For several days, on all sites I have visited with shopping carts, a low-opacity grey rectangle appears in the upper right hand corner of the screen. Nothing appearing on the screen covered by the rectangle will respond. And usually, the shopping cart button, and/or the search field are behind it.
I am forced to change to using Safari or Chrome if I am going to buy something (unless it's Amazon, that's the only shopping site I have used that seems to be free of this weird obstacle).