See https://github.com/nodejs/node/pull/34303/files#diff-7fba5f40db1aac2d3b08b083c268c8e7R686

Author: exoego

app/nodejs-v14/src/main/scala/io/scalajs/nodejs/worker_threads/WorkerOptions.scala

@@ -15,6 +15,8 @@ trait WorkerOptions extends js.Object {
   var stderr: js.UndefOr[Boolean]            = js.undefined
   var workerData: js.UndefOr[js.Any]         = js.undefined
 
+  @enableIf(io.scalajs.nodejs.internal.CompilerSwitches.gteNodeJs14)
+  var trackUnmanagedFds: js.UndefOr[Boolean] = js.undefined
   @enableIf(io.scalajs.nodejs.internal.CompilerSwitches.gteNodeJs14)
   var transferList: js.UndefOr[js.Array[js.Object]] = js.undefined