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diff --git a/devtools/shared/test-helpers/tracked-objects.sys.mjs b/devtools/shared/test-helpers/tracked-objects.sys.mjs
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+++ b/devtools/shared/test-helpers/tracked-objects.sys.mjs
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+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// Test-only module in order to register objects later inspected by
+// the allocation tracker (in the same folder).
+//
+// We are going to store a weak reference to the passed objects,
+// in order to prevent holding them in memory.
+// Allocation tracker will then print detailed information
+// about why these objects are still allocated.
+
+const objects = [];
+
+/**
+ * Request to track why the given object is kept in memory,
+ * later on, when retrieving all the watched object via getAllNodeIds.
+ */
+export function track(obj) {
+  // We store a weak reference, so that we do force keeping the object in memory!!
+  objects.push(Cu.getWeakReference(obj));
+}
+
+/**
+ * Return the NodeId's of all the objects passed via `track()` method.
+ *
+ * NodeId's are used by spidermonkey memory API to designates JS objects in head snapshots.
+ */
+export function getAllNodeIds() {
+  // Filter out objects which have been freed already
+  return (
+    objects
+      .map(weak => weak.get())
+      .filter(obj => !!obj)
+      // Convert objects from here instead of from allocation tracker in order
+      // to be from the shared system compartment and avoid trying to compute the NodeId
+      // of a wrapper!
+      .map(ChromeUtils.getObjectNodeId)
+  );
+}
+
+/**
+ * Used by tests to clear all tracked objects
+ */
+export function clear() {
+  objects.length = 0;
+}