documentObject: Document object for the document. If provided, it is used
directly without parsing the source again.
fragment: Fragmentation identifier (EPUB CFI) of the location in the
document which is to be displayed.
authorStyleSheet: An array of author style sheets to be injected after all
author style sheets referenced from the document. A single stylesheet may
be a URL of the style sheet or a text content of the style sheet.
userStyleSheet: An array of user style sheets to be injected.
A single stylesheet may be a URL of the style sheet or a text content of
the style sheet.
Options for the displayed document.