Since upgrading to 10.12.4 I have this issue with preview. Sometimes preview just shows blank (white) pages. Sometimes the page preview on the left side shows blanks, but the page is displayed correctly. Sometimes both show just blanks. With some PDF's it work as normal. Printing preview works correctly. This morning I downloaded Acrobat Reader, but I don't like it. It definitely is just a stopgap. What should I do next? Just wait for the next macOS update? Contact Apple?