My "new tab page" is always set to just blank page and has been for years. I dislike all the fancy new page stuff and just set it to blank page on initial install.

The sites that show up in the urlbar dropdown are frequently visited ones, same as the ones that show up when I turn the "update1" stuff off, or the ones prior to ff 75, just not sites containing amazon.co.uk.

So while I don't doubt your information, it doesn't make sense to me as an explanation. Maybe not having any sites in a new tab page is some kind of corner case that exposes a bug. It's weird that amazon is specifically affected though!