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>}`)
* Page render parameters.
 *
 * @typedef {Object} RenderParameters
 * @property {Object} canvasContext - A 2D context of a DOM Canvas object.
 * @property {PageViewport} viewport - Rendering viewport obtained by calling
 *   the `PDFPageProxy.getViewport` method.
 * @property {string} [intent] - Rendering intent, can be 'display' or 'print'.
 *   The default value is 'display'.
 * @property {boolean} [renderInteractiveForms] - Whether or not interactive
 *   form elements are rendered in the display layer. If so, we do not render
 *   them on the canvas as well. The default value is `false`.
 * @property {Array<any>} [transform] - Additional transform, applied just
 *   before viewport transform.
 * @property {Object} [imageLayer] - An object that has `beginLayout`,
 *   `endLayout` and `appendImage` functions.
 * @property {Object} [canvasFactory] - The factory instance that will be used
 *   when creating canvases. The default value is {new DOMCanvasFactory()}.
 * @property {Object | string} [background] - Background to use for the canvas.
 *   Any valid `canvas.fillStyle` can be used: a `DOMString` parsed as CSS
 *   <color> value, a `CanvasGradient` object (a linear or radial gradient) or
 *   a `CanvasPattern` object (a repetitive image). The default value is
 *   'rgb(255,255,255)'.
 * @property {boolean} [includeAnnotationStorage] - Render stored interactive
 *   form element data, from the {@link AnnotationStorage}-instance, onto the
 *   canvas itself; useful e.g. for printing. The default value is `false`.
 * @property {Promise<OptionalContentConfig>} [optionalContentConfigPromise] -
 *   A promise that should resolve with an {@link OptionalContentConfig}
 *   created from `PDFDocumentProxy.getOptionalContentConfig`. If `null`,
 *   the configuration will be fetched automatically with the default visibility
 *   states set.