Don't get me wrong, it's great that @calixteman wanted to implement that — JS should definitely be supported! I don't want to come off as rude or attacking.

For starters, JS reference specified in the [commit comment](https://github.com/mozilla/pdf.js/commit/8de98079ca05f8f7001ee077771055a57dc0e948) is outdated. It's version 8.1 from 2007… We're more than decade past that now. We should be implementing [Acrobat DC SDK](https://www.adobe.com/content/dam/acom/en/devnet/acrobat/pdfs/AcrobatDC_js_api_reference.pdf) ([here](https://help.adobe.com/en_US/acrobat/acrobat_dc_sdk/2015/HTMLHelp/#t=Acro12_MasterBook%2FJS_API_AcroJS%2FJavaScript_API.htm) in a nice HTML version).

Other than that, the Doc object now is only implemented with `info` property with standard fields (`Title`, `Author`, `Subject`, `Keywords`, `Creator`, `Producer`, `CreationDate`, `ModDate` and `Trapped`, case insensitive). But [according to the spec](https://www.adobe.com/content/dam/acom/en/devnet/acrobat/pdfs/AcrobatDC_js_api_reference.pdf#page=243) (even [in that old version](https://www.adobe.com/content/dam/acom/en/devnet/acrobat/pdfs/js_api_reference.pdf#page=243)), this object can contain other, non-standard properties, that can be set both in Acrobat interface and in JS (which are case-sensitive then).

Acrobat 9.0 introduced another field to that property, `Authors`, containing semicolon-delimited list of authors.

There are probably other problems with that code due to the outdated spec @calixteman was apparently working on.
import { PDFAttachmentViewer } from "./pdf_attachment_viewer.js";
import { PDFDocumentProperties } from "./pdf_document_properties.js";
import { PDFFindBar } from "./pdf_find_bar.js";
import { PDFFindController } from "./pdf_find_controller.js";
import { PDFHistory } from "./pdf_history.js";
import { PDFLayerViewer } from "./pdf_layer_viewer.js";
import { PDFLinkService } from "./pdf_link_service.js";
import { PDFOutlineViewer } from "./pdf_outline_viewer.js";
import { PDFPresentationMode } from "./pdf_presentation_mode.js";
import { PDFSidebar } from "./pdf_sidebar.js";
import { PDFSidebarResizer } from "./pdf_sidebar_resizer.js";
import { PDFThumbnailViewer } from "./pdf_thumbnail_viewer.js";
import { PDFViewer } from "./pdf_viewer.js";
import { SecondaryToolbar } from "./secondary_toolbar.js";
import { Toolbar } from "./toolbar.js";
import { viewerCompatibilityParams } from "./viewer_compatibility.js";
import { ViewHistory } from "./view_history.js";
const DEFAULT_SCALE_DELTA = 1.1;
const DISABLE_AUTO_FETCH_LOADING_BAR_TIMEOUT = 5000; 
const FORCE_PAGES_LOADED_TIMEOUT = 10000; 
const WHEEL_ZOOM_DISABLED_TIMEOUT = 1000; 
const ENABLE_PERMISSIONS_CLASS = "enablePermissions";
const ViewOnLoad = {
  UNKNOWN: -1,
  PREVIOUS: 0, 
  INITIAL: 1,
};
const ViewerCssTheme = {
  AUTOMATIC: 0, 
  LIGHT: 1,