It seems Blizzard and/or Xbox took a look at pop-up ads on websites and thought: “that’s a good idea, let’s put it into Diablo!”
In what is hopefully just a bug, players have been reporting getting stopped mid-Pit run or any other content by a pop-up telling them that the cash shop inventory has been updated. Agile-Peak-213 managed to grab a clip of it, and it’s exactly as annoying as you’d expect:
It’s certainly an easy click-off, especially on consoles, but it’s still pretty awful. It’s unclear whether this is only on Xbox or consoles in general, but there are multiple reports of players running into this.
That last comment seems to imply it’s happening on PC as well, on the Battle.net client.
Hopefully, this is just a bug and not a new marketing strategy to get players to visit the shop more often, because if it is a marketing tool, it’s one of the worst possible ones imaginable.