After hovering over an item with a very long tooltip (in my case Zerrick’s Guile) in one of the top stash rows the next item I hover over has its start of the tooltip moved to the top and out of the screen showing only a lower part of its tooltip.
https://i.imgur.com/VZd2IYq.png – Looking at Zerrick’s Guile (row 1, col 8)
https://i.imgur.com/ow1Rjsc.png – Immediatly hovering over the arena key next to it
Playing on a GeforceNow system on 1920x1080