--- a/dom/events/EventStateManager.cpp
+++ b/dom/events/EventStateManager.cpp
@@ -705,18 +705,17 @@ EventStateManager::PreHandleEvent(nsPres
   case eDragStart:
     if (Prefs::ClickHoldContextMenu()) {
       // an external drag gesture event came in, not generated internally
       // by Gecko. Make sure we get rid of the click-hold timer.
       KillClickHoldTimer();
     }
     break;
   case eDragOver:
-    // eDrop is fired before eLegacyDragDrop so send the enter/exit events
-    // before eDrop.
+    // Send the enter/exit events before eDrop.
     GenerateDragDropEnterExit(aPresContext, aEvent->AsDragEvent());
     break;
 
   case eKeyPress:
     {
       WidgetKeyboardEvent* keyEvent = aEvent->AsKeyboardEvent();
 
       int32_t modifierMask = 0;
@@ -1779,52 +1778,46 @@ EventStateManager::GenerateDragGesture(n
       // reset on the very next event to the correct frame).
 
       // Hold onto old target content through the event and reset after.
       nsCOMPtr<nsIContent> targetBeforeEvent = mCurrentTargetContent;
 
       // Set the current target to the content for the mouse down
       mCurrentTargetContent = targetContent;
 
-      // Dispatch both the dragstart and draggesture events to the DOM. For
-      // elements in an editor, only fire the draggesture event so that the
-      // editor code can handle it but content doesn't see a dragstart.
+      // Dispatch the dragstart event to the DOM.
       nsEventStatus status = nsEventStatus_eIgnore;
       EventDispatcher::Dispatch(targetContent, aPresContext, &startEvent,
                                 nullptr, &status);
 
       WidgetDragEvent* event = &startEvent;
 
       nsCOMPtr<nsIObserverService> observerService =
         mozilla::services::GetObserverService();
       // Emit observer event to allow addons to modify the DataTransfer object.
       if (observerService) {
         observerService->NotifyObservers(dataTransfer,
                                          "on-datatransfer-available",
                                          nullptr);
       }
 
       // now that the dataTransfer has been updated in the dragstart and
-      // draggesture events, make it readonly so that the data doesn't
+      // draggesture events, make it read only so that the data doesn't
       // change during the drag.
       dataTransfer->SetReadOnly();
 
       if (status != nsEventStatus_eConsumeNoDefault) {
         bool dragStarted = DoDefaultDragStart(aPresContext, event, dataTransfer,
                                               targetContent, selection);
         if (dragStarted) {
           sActiveESM = nullptr;
           aEvent->StopPropagation();
         }
       }
 
-      // Note that frame event handling doesn't care about eLegacyDragGesture,
-      // which is just as well since we don't really know which frame to
-      // send it to
-
       // Reset mCurretTargetContent to what it was
       mCurrentTargetContent = targetBeforeEvent;
     }
 
     // Now flush all pending notifications, for better responsiveness
     // while dragging.
     FlushPendingEvents(aPresContext);
   }
@@ -1919,17 +1912,17 @@ EventStateManager::DoDefaultDragStart(ns
                                       nsIContent* aDragTarget,
                                       nsISelection* aSelection)
 {
   nsCOMPtr<nsIDragService> dragService =
     do_GetService("@mozilla.org/widget/dragservice;1");
   if (!dragService)
     return false;
 
-  // Default handling for the draggesture/dragstart event.
+  // Default handling for the dragstart event.
   //
   // First, check if a drag session already exists. This means that the drag
   // service was called directly within a draggesture handler. In this case,
   // don't do anything more, as it is assumed that the handler is managing
   // drag and drop manually. Make sure to return true to indicate that a drag
   // began.
   nsCOMPtr<nsIDragSession> dragSession;
   dragService->GetCurrentSession(getter_AddRefs(dragSession));

--- a/dom/events/EventStateManager.h
+++ b/dom/events/EventStateManager.h
@@ -850,21 +850,21 @@ protected:
    */
   void DetermineDragTargetAndDefaultData(nsPIDOMWindowOuter* aWindow,
                                          nsIContent* aSelectionTarget,
                                          dom::DataTransfer* aDataTransfer,
                                          nsISelection** aSelection,
                                          nsIContent** aTargetNode);
 
   /*
-   * Perform the default handling for the dragstart/draggesture event and set up a
+   * Perform the default handling for the dragstart event and set up a
    * drag for aDataTransfer if it contains any data. Returns true if a drag has
    * started.
    *
-   * aDragEvent - the dragstart/draggesture event
+   * aDragEvent - the dragstart event
    * aDataTransfer - the data transfer that holds the data to be dragged
    * aDragTarget - the target of the drag
    * aSelection - the selection to be dragged
    */
   bool DoDefaultDragStart(nsPresContext* aPresContext,
                           WidgetDragEvent* aDragEvent,
                           dom::DataTransfer* aDataTransfer,
                           nsIContent* aDragTarget,