diff --git a/reviewboard/static/rb/js/views/dndUploaderView.es6.js b/reviewboard/static/rb/js/views/dndUploaderView.es6.js
index 1f8731ca5d4e01be6225bebbb91bed5be8c5d416..fa5a6fcc67625d14e05e55e32146b3c7f6246b1d 100644
--- a/reviewboard/static/rb/js/views/dndUploaderView.es6.js
+++ b/reviewboard/static/rb/js/views/dndUploaderView.es6.js
@@ -301,7 +301,7 @@ RB.DnDUploader = Backbone.View.extend({
      *         The event that triggered the callback.
      */
     _showOverlays(e) {
-        if (e.originalEvent.dataTransfer !== undefined &&
+        if (!$('.modalbox')[0] && e.originalEvent.dataTransfer !== undefined &&
             Array.from(e.originalEvent.dataTransfer.types).includes('Files')) {
             this._overlaysHiding = false;