I am using one of the fda forms(FDA 1572) found here Clinical Trial Forms | FDA, which has a dynamic add-extra-page button, which should add extra pages. It works on adobe reader but does not work on pdfjs express webviewer. This is the error I get when I click the button :
Embedded JS error encountered, Mouse Up event on Field: ReferenceError: AddPage is not defined
// VCK 5/26/13
//
// Continuation button for section 3 spawns T3-1.
// Don’t add a page 3 if it has already been added.