diff --git ui/base/dragdrop/os_exchange_data_provider_aurax11.cc ui/base/dragdrop/os_exchange_data_provider_aurax11.cc
index 1a6e9a1..08eb800 100644
--- ui/base/dragdrop/os_exchange_data_provider_aurax11.cc
+++ ui/base/dragdrop/os_exchange_data_provider_aurax11.cc
@@ -141,7 +141,8 @@ void OSExchangeDataProviderAuraX11::SetURL(const GURL& url,
     format_map_.Insert(gfx::GetAtom(Clipboard::kMimeTypeMozillaURL), mem);
 
     // Set a string fallback as well.
-    SetString(spec);
+    if (!HasString())
+      SetString(spec);
 
     // Return early if this drag already contains file contents (this implies
     // that file contents must be populated before URLs). Nautilus (and possibly