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>}`)
return shadow(this, "annotationStorage", new AnnotationStorage());
  }
  destroy() {
    if (this.destroyCapability) {
      return this.destroyCapability.promise;
    }
    this.destroyed = true;
    this.destroyCapability = createPromiseCapability();
    if (this._passwordCapability) {
      this._passwordCapability.reject(
        new Error("Worker was destroyed during onPassword callback")
      );
    }
    const waitOn = [];
    
    
    for (const page of this.pageCache) {
      if (page) {