diff --git a/dom/base/nsJSUtils.cpp b/dom/base/nsJSUtils.cpp
index 65965d74bf..2601ffd87f 100644
--- a/dom/base/nsJSUtils.cpp
+++ b/dom/base/nsJSUtils.cpp
@@ -315,7 +315,8 @@ nsJSUtils::ModuleInstantiate(JSContext* aCx, JS::Handle<JSObject*> aModule)
 
   MOZ_ASSERT(aCx == nsContentUtils::GetCurrentJSContext());
   MOZ_ASSERT(NS_IsMainThread());
-  MOZ_ASSERT(nsContentUtils::IsInMicroTask());
+  MOZ_ASSERT(CycleCollectedJSContext::Get() &&
+             CycleCollectedJSContext::Get()->MicroTaskLevel());
 
   NS_ENSURE_TRUE(xpc::Scriptability::Get(aModule).Allowed(), NS_OK);