P: Alt+delete shortcut expands layer around artboards

(This is in Photoshop CC only) using the alt+delete or cmd+delete to fill a layer on the second artboard or above causes that layer to expand to include all the other artboards. The color does not affect the other artboards but it is very frustrating to see such a large image outside the artboard and also when trying to align other objects. This image shows the bounding box, which should only encompass the bottom left artboard, extending out over all the others.