diff --git a/widget/ContentCache.cpp b/widget/ContentCache.cpp
index add67fa6f5b..4a11f52b57e 100644
--- a/widget/ContentCache.cpp
+++ b/widget/ContentCache.cpp
@@ -510,7 +510,6 @@ ContentCacheInParent::HandleQueryContentEvent(WidgetQueryContentEvent& aEvent,
   MOZ_ASSERT(aWidget);
 
   aEvent.mSucceeded = false;
-  aEvent.mWasAsync = false;
   aEvent.mReply.mFocusedWidget = aWidget;
 
   switch (aEvent.message) {
diff --git a/widget/TextEvents.h b/widget/TextEvents.h
index 2ffbee55416..cd271771436 100644
--- a/widget/TextEvents.h
+++ b/widget/TextEvents.h
@@ -464,7 +464,6 @@ public:
                           nsIWidget* aWidget)
     : WidgetGUIEvent(aIsTrusted, aMessage, aWidget, eQueryContentEventClass)
     , mSucceeded(false)
-    , mWasAsync(false)
     , mUseNativeLineBreak(true)
     , mWithFontRanges(false)
   {
@@ -546,7 +545,6 @@ public:
   }
 
   bool mSucceeded;
-  bool mWasAsync;
   bool mUseNativeLineBreak;
   bool mWithFontRanges;
   struct
diff --git a/widget/android/nsWindow.cpp b/widget/android/nsWindow.cpp
index 6db063b302f..32269163f80 100644
--- a/widget/android/nsWindow.cpp
+++ b/widget/android/nsWindow.cpp
@@ -1895,7 +1895,7 @@ nsWindow::OnIMEEvent(AndroidGeckoEvent *ae)
                                               this);
                 InitEvent(event, nullptr);
                 DispatchEvent(&event);
-                MOZ_ASSERT(event.mSucceeded && !event.mWasAsync);
+                MOZ_ASSERT(event.mSucceeded);
 
                 if (start < 0)
                     start = int32_t(event.GetSelectionStart());
@@ -1978,7 +1978,7 @@ nsWindow::OnIMEEvent(AndroidGeckoEvent *ae)
                                                        this);
                     InitEvent(queryEvent, nullptr);
                     DispatchEvent(&queryEvent);
-                    MOZ_ASSERT(queryEvent.mSucceeded && !queryEvent.mWasAsync);
+                    MOZ_ASSERT(queryEvent.mSucceeded);
                     event.mData = queryEvent.mReply.mString;
                 }
 
diff --git a/widget/nsGUIEventIPC.h b/widget/nsGUIEventIPC.h
index 1e55d91e3e9..fd0199005a7 100644
--- a/widget/nsGUIEventIPC.h
+++ b/widget/nsGUIEventIPC.h
@@ -597,7 +597,6 @@ struct ParamTraits<mozilla::WidgetQueryContentEvent>
 
   static bool Read(const Message* aMsg, void** aIter, paramType* aResult)
   {
-    aResult->mWasAsync = true;
     return ReadParam(aMsg, aIter,
                      static_cast<mozilla::WidgetGUIEvent*>(aResult)) &&
            ReadParam(aMsg, aIter, &aResult->mSucceeded) &&