disable default drag handling

NoopDragHandler.cs

@@ -0,0 +1,23 @@
+// Copyright(c) 2019 pypy. All rights reserved.
+//
+// This work is licensed under the terms of the MIT license.
+// For a copy, see <https://opensource.org/licenses/MIT>.
+
+using System.Collections.Generic;
+using CefSharp;
+using CefSharp.Enums;
+
+namespace VRCX
+{
+    public class NoopDragHandler : IDragHandler
+    {
+        bool IDragHandler.OnDragEnter(IWebBrowser chromiumWebBrowser, IBrowser browser, IDragData dragData, DragOperationsMask mask)
+        {
+            return true;
+        }
+
+        void IDragHandler.OnDraggableRegionsChanged(IWebBrowser chromiumWebBrowser, IBrowser browser, IFrame frame, IList<DraggableRegion> regions)
+        {
+        }
+    }
+}