--- a/dom/base/nsObjectLoadingContent.cpp
+++ b/dom/base/nsObjectLoadingContent.cpp
@@ -6,16 +6,17 @@
 /*
  * A base class implementing nsIObjectLoadingContent for use by
  * various content nodes that want to provide plugin/document/image
  * loading functionality (eg <embed>, <object>, <applet>, etc).
  */
 
 // Interface headers
 #include "imgLoader.h"
+#include "nsIClassOfService.h"
 #include "nsIConsoleService.h"
 #include "nsIContent.h"
 #include "nsIContentInlines.h"
 #include "nsIDocShell.h"
 #include "nsIDocument.h"
 #include "nsIDOMCustomEvent.h"
 #include "nsIDOMDocument.h"
 #include "nsIDOMHTMLObjectElement.h"
@@ -79,16 +80,17 @@
 #include "mozilla/BasicEvents.h"
 #include "mozilla/dom/BindingUtils.h"
 #include "mozilla/dom/Element.h"
 #include "mozilla/dom/Event.h"
 #include "mozilla/dom/ScriptSettings.h"
 #include "mozilla/dom/PluginCrashedEvent.h"
 #include "mozilla/AsyncEventDispatcher.h"
 #include "mozilla/EventDispatcher.h"
+#include "mozilla/EventStateManager.h"
 #include "mozilla/EventStates.h"
 #include "mozilla/IntegerPrintfMacros.h"
 #include "mozilla/dom/HTMLObjectElementBinding.h"
 #include "mozilla/dom/HTMLSharedObjectElement.h"
 #include "mozilla/dom/HTMLObjectElement.h"
 #include "nsChannelClassifier.h"
 
 #ifdef XP_WIN
@@ -2543,16 +2545,21 @@ nsObjectLoadingContent::OpenChannel()
                                          doc->GetReferrerPolicy());
     MOZ_ASSERT(NS_SUCCEEDED(rv));
 
     // Set the initiator type
     nsCOMPtr<nsITimedChannel> timedChannel(do_QueryInterface(httpChan));
     if (timedChannel) {
       timedChannel->SetInitiatorType(thisContent->LocalName());
     }
+
+    nsCOMPtr<nsIClassOfService> cos(do_QueryInterface(httpChan));
+    if (cos && EventStateManager::IsHandlingUserInput()) {
+      cos->AddClassFlags(nsIClassOfService::UrgentStart);
+    }
   }
 
   nsCOMPtr<nsIScriptChannel> scriptChannel = do_QueryInterface(chan);
   if (scriptChannel) {
     // Allow execution against our context if the principals match
     scriptChannel->SetExecutionPolicy(nsIScriptChannel::EXECUTE_NORMAL);
   }