diff --git a/sao/src/view/tree.js b/sao/src/view/tree.js
index 43b86f7636..d55b64dc4f 100644
--- a/sao/src/view/tree.js
+++ b/sao/src/view/tree.js
@@ -916,7 +916,7 @@
                     this.display_size = Sao.config.display_size;
                 }
             }
-            if (!this.display_size &
+            if (!this.display_size &&
                 (!jQuery.isEmptyObject(selected) ||
                     !jQuery.isEmptyObject(expanded))) {
                 this.display_size = Sao.config.display_size;