diff --git a/dom/script/ScriptLoader.cpp b/dom/script/ScriptLoader.cpp
index 6e385dd9df..e84ebcf151 100644
--- a/dom/script/ScriptLoader.cpp
+++ b/dom/script/ScriptLoader.cpp
@@ -89,6 +89,7 @@ ScriptFetchOptions::ScriptFetchOptions(mozilla::CORSMode aCORSMode,
                                        nsIPrincipal* aTriggeringPrincipal)
   : mCORSMode(aCORSMode)
   , mReferrerPolicy(aReferrerPolicy)
+  , mIsPreload(false)
   , mElement(aElement)
   , mTriggeringPrincipal(aTriggeringPrincipal)
 {
@@ -1110,7 +1111,7 @@ ScriptLoader::ProcessLoadedModuleTree(ModuleLoadRequest* aRequest)
       RefPtr<ScriptLoadRequest> req = mDynamicImportRequests.Steal(aRequest);
       RunScriptWhenSafe(req);
     } else if (aRequest->mIsInline &&
-               aRequest->Element()->GetParserCreated() == NOT_FROM_PARSER) {
+               aRequest->GetParserCreated() == NOT_FROM_PARSER) {
         RunScriptWhenSafe(aRequest);
     } else {
       MaybeMoveToLoadedList(aRequest);
@@ -1510,7 +1511,7 @@ ScriptLoader::ProcessScriptElement(nsIScriptElement *aElement)
       // preloaded
       // note that a script-inserted script can steal a preload!
       request = mPreloads[i].mRequest;
-      request->SetElement(aElement);
+      request->SetIsLoadRequest(aElement);
       nsString preloadCharset(mPreloads[i].mCharset);
       mPreloads.RemoveElementAt(i);
 
@@ -1981,7 +1982,7 @@ ScriptLoader::ProcessRequest(ScriptLoadRequest* aRequest)
   }
 
   nsCOMPtr<nsIScriptElement> oldParserInsertedScript;
-  uint32_t parserCreated = aRequest->Element()->GetParserCreated();
+  uint32_t parserCreated = aRequest->GetParserCreated();
   if (parserCreated) {
     oldParserInsertedScript = mCurrentParserInsertedScript;
     mCurrentParserInsertedScript = aRequest->Element();
@@ -2192,15 +2193,15 @@ ScriptLoader::EvaluateScript(ScriptLoadRequest* aRequest)
   }
 
   nsCOMPtr<nsIContent> scriptContent(do_QueryInterface(aRequest->Element()));
-  nsIDocument* ownerDoc = scriptContent->OwnerDoc();
-  if (ownerDoc != mDocument) {
-    // Willful violation of HTML5 as of 2010-12-01
-    return NS_ERROR_FAILURE;
+  MOZ_ASSERT_IF(!scriptContent, aRequest->AsModuleRequest()->IsDynamicImport());
+  if (scriptContent) {
+    nsIDocument* ownerDoc = scriptContent->OwnerDoc();
+    if (ownerDoc != mDocument) {
+      // Willful violation of HTML5 as of 2010-12-01
+      return NS_ERROR_FAILURE;
+    }
   }
 
-  // Get the script-type to be used by this element.
-  NS_ASSERTION(scriptContent, "no content - what is default script-type?");
-
   nsCOMPtr<nsIScriptGlobalObject> globalObject = GetScriptGlobalObject();
   if (!globalObject) {
     return NS_ERROR_FAILURE;
@@ -2955,6 +2956,7 @@ ScriptLoader::PreloadURI(nsIURI *aURI,
                       aReferrerPolicy);
   request->mIsInline = false;
   request->SetScriptMode(aDefer, aAsync);
+  request->SetIsPreloadRequest();
 
   nsresult rv = StartLoad(request, aType, aScriptFromHead);
   if (NS_FAILED(rv)) {
diff --git a/dom/script/ScriptLoader.h b/dom/script/ScriptLoader.h
index 2e2b1592cd..da39d0a630 100644
--- a/dom/script/ScriptLoader.h
+++ b/dom/script/ScriptLoader.h
@@ -70,6 +70,7 @@ public:
 
   const mozilla::CORSMode mCORSMode;
   const mozilla::net::ReferrerPolicy mReferrerPolicy;
+  bool mIsPreload;
   nsCOMPtr<nsIScriptElement> mElement;
   nsCOMPtr<nsIPrincipal> mTriggeringPrincipal;
 };
@@ -113,9 +114,9 @@ public:
     Element()->ScriptEvaluated(aResult, Element(), mIsInline);
   }
 
-  bool IsPreload()
-  {
-    return Element() == nullptr;
+  bool IsPreload() const {
+    MOZ_ASSERT_IF(mFetchOptions->mIsPreload, !Element());
+    return mFetchOptions->mIsPreload;
   }
 
   virtual void Cancel();
@@ -195,13 +196,32 @@ public:
     return mFetchOptions->mTriggeringPrincipal;
   }
 
-  void SetElement(nsIScriptElement* aElement)
+  // Make this request a preload (speculative) request.
+  void SetIsPreloadRequest()
+  {
+    MOZ_ASSERT(!Element());
+    MOZ_ASSERT(!IsPreload());
+    mFetchOptions->mIsPreload = true;
+  }
+
+  // Make a preload request into an actual load request for the given element.
+  void SetIsLoadRequest(nsIScriptElement* aElement)
   {
-    // Called when a preload request is later used for an actual request.
     MOZ_ASSERT(aElement);
     MOZ_ASSERT(!Element());
+    MOZ_ASSERT(IsPreload());
     mFetchOptions->mElement = aElement;
-   }
+    mFetchOptions->mIsPreload = false;
+  }
+
+  FromParser GetParserCreated() const 
+  {
+    nsIScriptElement* element = Element();
+    if (!element) {
+      return NOT_FROM_PARSER;
+    }
+    return element->GetParserCreated();
+  }
 
   void SetScript(JSScript* aScript);