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>}`)
fallbackWorkerSrc = pdfjsFilePath.replace(
          /(\.(?:min\.)?js)(\?.*)?$/i,
          ".worker$1$2"
        );
      }
    }
  }
  function getWorkerSrc() {
    if (GlobalWorkerOptions.workerSrc) {
      return GlobalWorkerOptions.workerSrc;
    }
    if (typeof fallbackWorkerSrc !== "undefined") {
      if (!isNodeJS) {
        deprecated('No "GlobalWorkerOptions.workerSrc" specified.');
      }
      return fallbackWorkerSrc;
    }
    throw new Error('No "GlobalWorkerOptions.workerSrc" specified.');
  }
  function getMainThreadWorkerMessageHandler() {
    let mainWorkerMessageHandler;
    try {
      mainWorkerMessageHandler = globalThis.pdfjsWorker?.WorkerMessageHandler;
    } catch (ex) {
      
    }
    return mainWorkerMessageHandler || null;
  }
  
  function setupFakeWorkerGlobal() {