Hi,
Please replace the following lines in the plugin WPDM extended shortcodes, you can find the file at plugins/wpdm-extended-shortcodes/wpdm-extended-shortcodes.php
line 416 echo "<ul class='jqueryFileTree' style='display: initial;'>";
line 426 echo "<li class='directory expanded'><a href='#' rel='" . $cat->term_id . "'>" . $cat->name . "</a></li>";
Thanks