--- a/js/src/jsobj.cpp
+++ b/js/src/jsobj.cpp
@@ -1798,17 +1798,17 @@ js::CloneObject(JSContext *cx, HandleObj
         }
 
         if (obj->as<NativeObject>().hasPrivate())
             clone->as<NativeObject>().setPrivate(obj->as<NativeObject>().getPrivate());
     } else {
         ProxyOptions options;
         options.setClass(obj->getClass());
 
-        clone = ProxyObject::New(cx, GetProxyHandler(obj), JS::NullHandleValue, proto, nullptr, options);
+        clone = ProxyObject::New(cx, GetProxyHandler(obj), JS::NullHandleValue, proto, options);
         if (!clone)
             return nullptr;
 
         if (!CopyProxyObject(cx, obj.as<ProxyObject>(), clone.as<ProxyObject>()))
             return nullptr;
     }
 
     return clone;

--- a/js/src/proxy/Proxy.cpp
+++ b/js/src/proxy/Proxy.cpp
@@ -730,18 +730,17 @@ JS_FRIEND_API(JSObject *)
 js::NewProxyObject(JSContext *cx, const BaseProxyHandler *handler, HandleValue priv, JSObject *proto_,
                    const ProxyOptions &options)
 {
     if (options.lazyProto()) {
         MOZ_ASSERT(!proto_);
         proto_ = TaggedProto::LazyProto;
     }
 
-    return ProxyObject::New(cx, handler, priv, TaggedProto(proto_), nullptr,
-                            options);
+    return ProxyObject::New(cx, handler, priv, TaggedProto(proto_), options);
 }
 
 void
 ProxyObject::renew(JSContext *cx, const BaseProxyHandler *handler, Value priv)
 {
     MOZ_ASSERT_IF(IsCrossCompartmentWrapper(this), IsDeadProxyObject(this));
     MOZ_ASSERT(getParent() == cx->global());
     MOZ_ASSERT(getClass() == &ProxyObject::class_);

--- a/js/src/vm/ProxyObject.cpp
+++ b/js/src/vm/ProxyObject.cpp
@@ -9,26 +9,24 @@
 #include "jscompartment.h"
 #include "jsgcinlines.h"
 #include "jsobjinlines.h"
 
 using namespace js;
 
 /* static */ ProxyObject *
 ProxyObject::New(JSContext *cx, const BaseProxyHandler *handler, HandleValue priv, TaggedProto proto_,
-                 JSObject *parent_, const ProxyOptions &options)
+                 const ProxyOptions &options)
 {
     Rooted<TaggedProto> proto(cx, proto_);
-    RootedObject parent(cx, parent_);
 
     const Class *clasp = options.clasp();
 
     MOZ_ASSERT(isValidProxyClass(clasp));
     MOZ_ASSERT_IF(proto.isObject(), cx->compartment() == proto.toObject()->compartment());
-    MOZ_ASSERT_IF(parent, cx->compartment() == parent->compartment());
 
     /*
      * Eagerly mark properties unknown for proxies, so we don't try to track
      * their properties and so that we don't need to walk the compartment if
      * their prototype changes later.  But don't do this for DOM proxies,
      * because we want to be able to keep track of them in typesets in useful
      * ways.
      */
@@ -45,17 +43,17 @@ ProxyObject::New(JSContext *cx, const Ba
         allocKind = GetBackgroundAllocKind(allocKind);
 
     ProxyValueArray *values = cx->zone()->new_<ProxyValueArray>();
     if (!values)
         return nullptr;
 
     // Note: this will initialize the object's |data| to strange values, but we
     // will immediately overwrite those below.
-    RootedObject obj(cx, NewObjectWithGivenTaggedProto(cx, clasp, proto, parent, allocKind,
+    RootedObject obj(cx, NewObjectWithGivenTaggedProto(cx, clasp, proto, NullPtr(), allocKind,
                                                        newKind));
     if (!obj) {
         js_free(values);
         return nullptr;
     }
 
     Rooted<ProxyObject*> proxy(cx, &obj->as<ProxyObject>());
 

--- a/js/src/vm/ProxyObject.h
+++ b/js/src/vm/ProxyObject.h
@@ -23,18 +23,17 @@ class ProxyObject : public JSObject
         static_assert(sizeof(ProxyObject) == sizeof(JSObject_Slots0),
                       "proxy object size must match GC thing size");
         static_assert(offsetof(ProxyObject, data) == ProxyDataOffset,
                       "proxy object layout must match shadow interface");
     }
 
   public:
     static ProxyObject *New(JSContext *cx, const BaseProxyHandler *handler, HandleValue priv,
-                            TaggedProto proto_, JSObject *parent_,
-                            const ProxyOptions &options);
+                            TaggedProto proto_, const ProxyOptions &options);
 
     const Value &private_() {
         return GetProxyPrivate(this);
     }
 
     void setCrossCompartmentPrivate(const Value &priv);
     void setSameCompartmentPrivate(const Value &priv);