Why are Annotation thumbnails missing from the Annotations summary page of a Multi Page Document?
This issue may occur when a Multi Page Document has two or more differing page sizes, with varying vertical and/or horizontal page dimensions.
The problem is related to the Normalization of a Graphics. The OBGE (Automation Engine) component cannot currently pass along the XMP margin data per page. This data is needed in order for WebCenter to render the thumbnails as is common with other Graphic Documents.
Solved in 16.1 r13 (make sure also the OBGE is on 16.0.2).
Solution for files uploaded before and therefore still with missing view icons : regenerate viewfiles.