diff --git a/devtools/server/main.js b/devtools/server/main.js
index ac76adb831..4af1381896 100644
--- a/devtools/server/main.js
+++ b/devtools/server/main.js
@@ -1462,7 +1462,9 @@ DebuggerServerConnection.prototype = {
   },
 
   send(packet) {
-    this.transport.send(packet);
+    if (this.transport) {
+      this.transport.send(packet);
+    }
   },
 
   /**