canvasMaxAreaInBytes in DocumentInitParameters has type Boolean, preventing TypeScript users from passing the correct (numeric) value.
return this.messageHandler.sendWithPromise("GetViewerPreferences", null);
  }
  getOpenAction() {
    return this.messageHandler.sendWithPromise("GetOpenAction", null);
  }
  getAttachments() {
    return this.messageHandler.sendWithPromise("GetAttachments", null);
  }
  getJavaScript() {
    return this.messageHandler.sendWithPromise("GetJavaScript", null);
  }
  getDocJSActions() {
    return this.messageHandler.sendWithPromise("GetDocJSActions", null);
  }
  getPageJSActions(pageIndex) {
    return this.messageHandler.sendWithPromise("GetPageJSActions", {
      pageIndex,
    });
  }
  getStructTree(pageIndex) {
    return this.messageHandler.sendWithPromise("GetStructTree", {
      pageIndex,
    });
  }
  getOutline() {
    return this.messageHandler.sendWithPromise("GetOutline", null);
  }
  getOptionalContentConfig() {