slim crown
i dont know if its intentional or not but its only really noticable when it starts to lag a lil or when the emote goes to the edge of the preview like in the screenshot
its been a thing since the features release but i figure id make a post about it now (chrome webstore)
humble agate
this is kinda just how the feature works, theres not really a reason to hide the thumbnail behind the 3d render because it should always be covered