Please see the screenshots. AP show images 1px bigger on 100% view, so right and bottom will be cropped by 1px.
Saved image is correct size, so it's just shown incorrectly in AP.
*ap-screenshot1.png
Right and bottom border is cut out.
*ap-screenshot2.png
As you see boundary box goes outside of the canvas.
*bordered-box.png
Actual image data.