diff --git a/js/src/jsgc.cpp b/js/src/jsgc.cpp
index ca605c35d2d2..a0ebb8afdea2 100644
--- a/js/src/jsgc.cpp
+++ b/js/src/jsgc.cpp
@@ -2800,6 +2800,8 @@ GCRuntime::updatePointersToRelocatedCells(Zone* zone)
     callWeakPointerZoneGroupCallbacks();
     for (CompartmentsInZoneIter comp(zone); !comp.done(); comp.next())
         callWeakPointerCompartmentCallbacks(comp);
+    if (rt->sweepZoneCallback)
+        rt->sweepZoneCallback(zone);
 }
 
 void