I am unsure if this is known or covered but I couldn't find anything on it when searching through posts.
when scrolling boxes to the left, the wallpaper of the box you're currently looking at is incorrectly displayed in a section of the pokemon's viewing area at the left of the screen.
When moving your box to the right, no glitchy sprite appears.
https://www.youtube.com/watch?v=4lql1_DPDsg&feature=youtu.be
This also seems to happen when changing the name of the box, but now it takes the sprite of the boxname area instead.
I was working on a different glitch I called the 'instant boxing glitch', which Charmy helped me test.
When looking at a screenshot, I randomly noticed this very minor oddity;
I believe this occurs because this area is supposed to be seethrough but messes up the updating process.