diff --git a/js/misc/signalTracker.js b/js/misc/signalTracker.js
index 1c3f4f9df..8444564df 100644
--- a/js/misc/signalTracker.js
+++ b/js/misc/signalTracker.js
@@ -42,7 +42,7 @@ class SignalManager {
     }
 
     constructor() {
-        this._signalTrackers = new Map();
+        this._signalTrackers = new WeakMap();
     }
 
     /**