--- a/js/xpconnect/wrappers/AddonWrapper.cpp
+++ b/js/xpconnect/wrappers/AddonWrapper.cpp
@@ -37,28 +37,18 @@ ReportASCIIErrorWithId(JSContext* cx, co
         return;
     JS_ReportErrorUTF8(cx, msg, bytes.ptr());
 }
 
 bool
 InterposeProperty(JSContext* cx, HandleObject target, const nsIID* iid, HandleId id,
                   MutableHandle<PropertyDescriptor> descriptor)
 {
-    // We only want to do interpostion on DOM instances and
-    // wrapped natives.
     RootedObject unwrapped(cx, UncheckedUnwrap(target));
-    const js::Class* clasp = js::GetObjectClass(unwrapped);
     bool isCPOW = jsipc::IsWrappedCPOW(unwrapped);
-    if (!mozilla::dom::IsDOMClass(clasp) &&
-        !IS_WN_CLASS(clasp) &&
-        !IS_PROTO_CLASS(clasp) &&
-        clasp != &OuterWindowProxyClass &&
-        !isCPOW) {
-        return true;
-    }
 
     XPCWrappedNativeScope* scope = ObjectScope(CurrentGlobalOrNull(cx));
     MOZ_ASSERT(scope->HasInterposition());
 
     nsCOMPtr<nsIAddonInterposition> interp = scope->GetInterposition();
     InterpositionWhitelist* wl = XPCWrappedNativeScope::GetInterpositionWhitelist(interp);
     // We do InterposeProperty only if the id is on the whitelist of the interpostion
     // or if the target is a CPOW.