Start with default generated template

templates/content-edit/file-widget-multiple.html.twig

@@ -0,0 +1,14 @@
+{#
+/**
+ * @file
+ * Theme override to display a multi file form widget.
+ *
+ * Available variables:
+ * - table: Table of previously uploaded files.
+ * - element: The form element for uploading another file.
+ *
+ * @see template_preprocess_file_widget_multiple()
+ */
+#}
+{{ table }}
+{{ element }}