diff --git a/widget/nsTransferable.cpp b/widget/nsTransferable.cpp
index 28d54240e33b..543ff912afbe 100644
--- a/widget/nsTransferable.cpp
+++ b/widget/nsTransferable.cpp
@@ -36,6 +36,7 @@ Notes to self:
 #include "nsIWeakReferenceUtils.h"
 #include "nsIFile.h"
 #include "nsILoadContext.h"
+#include "mozilla/UniquePtr.h"
 
 NS_IMPL_ISUPPORTS(nsTransferable, nsITransferable)
 
@@ -183,7 +184,7 @@ DataStruct::ReadCache(nsISupports** aData, uint32_t* aDataLen)
 
     uint32_t size = uint32_t(fileSize);
     // create new memory for the large clipboard data
-    auto data = MakeUnique<char[]>(size);
+    auto data = mozilla::MakeUnique<char[]>(size);
     if ( !data )
       return NS_ERROR_OUT_OF_MEMORY;