diff --git a/src/display/api.js b/src/display/api.js
index 08b34aa46..e05a747f3 100644
--- a/src/display/api.js
+++ b/src/display/api.js
@@ -2077,7 +2077,10 @@ class PDFWorker {
     this._webWorker = null;
     this._messageHandler = null;
 
-    if (port) {
+    if (
+      (typeof PDFJSDev === "undefined" || !PDFJSDev.test("MOZCENTRAL")) &&
+      port
+    ) {
       if (PDFWorker.#workerPorts.has(port)) {
         throw new Error("Cannot use more than one PDFWorker per port.");
       }
@@ -2113,6 +2116,9 @@ class PDFWorker {
   }
 
   _initializeFromPort(port) {
+    if (typeof PDFJSDev !== "undefined" && PDFJSDev.test("MOZCENTRAL")) {
+      throw new Error("Not implemented: _initializeFromPort");
+    }
     this._port = port;
     this._messageHandler = new MessageHandler("main", "worker", port);
     this._messageHandler.on("ready", function () {