--- a/js/xpconnect/src/XPCJSContext.cpp
+++ b/js/xpconnect/src/XPCJSContext.cpp
@@ -3526,16 +3526,20 @@ XPCJSContext::Initialize()
     RegisterJSMainRuntimeCompartmentsSystemDistinguishedAmount(JSMainRuntimeCompartmentsSystemDistinguishedAmount);
     RegisterJSMainRuntimeCompartmentsUserDistinguishedAmount(JSMainRuntimeCompartmentsUserDistinguishedAmount);
     mozilla::RegisterJSSizeOfTab(JSSizeOfTab);
 
     // Watch for the JS boolean options.
     ReloadPrefsCallback(nullptr, this);
     Preferences::RegisterCallback(ReloadPrefsCallback, JS_OPTIONS_DOT_STR, this);
 
+#ifdef FUZZING
+    Preferences::RegisterCallback(ReloadPrefsCallback, "fuzzing.enabled", this);
+#endif
+
     return NS_OK;
 }
 
 // static
 XPCJSContext*
 XPCJSContext::newXPCJSContext()
 {
     XPCJSContext* self = new XPCJSContext();