https://github.com/mozilla/pdf.js/blob/0df1a5661958df0c4ed2f73b0f3266d825c5c280/src/display/api.js#L710-L719
The return type signature `@returns {Promise<{num: number, gen: number}>}` is mismatched with its definition. (should be `@returns {Promise<number>}`)
* @property {string} fontName - Font name used by PDF.js for converted font.
 *
 */
/**
 * Page text marked content part.
 *
 * @typedef {Object} TextMarkedContent
 * @property {string} type - Either 'beginMarkedContent',
 *   'beginMarkedContentProps', or 'endMarkedContent'.
 * @property {string} id - The marked content identifier. Only used for type
 *   'beginMarkedContentProps'.
 */
/**
 * Text style.
 *
 * @typedef {Object} TextStyle
 * @property {number} ascent - Font ascent.
 * @property {number} descent - Font descent.
 * @property {boolean} vertical - Whether or not the text is in vertical mode.
 * @property {string} fontFamily - The possible font family.
 */
/**
 * Page annotation parameters.
 *
 * @typedef {Object} GetAnnotationsParameters
 * @property {string} intent - Determines the annotations that will be fetched,
 *   can be either 'display' (viewable annotations) or 'print' (printable
 *   annotations). If the parameter is omitted, all annotations are fetched.
 */
/**