Gets the objects the first-page cross-reference section lists, in object number order: the linearization parameter dictionary, the catalog and the other document-level objects needed at open, the first page's objects and the primary hint stream. Empty when the file's original revision has no separate first-page section.
public IReadOnlyList<CosReference> FirstPageObjects { get; }
ISO 32000-2 F.3.4, F.3.5 and F.3.6 (parts 2 to 6 of a linearized file).