diff --git a/htdocs/core/lib/functions.lib.php b/htdocs/core/lib/functions.lib.php
index 412a3c89be7..33e3df9cb74 100644
--- a/htdocs/core/lib/functions.lib.php
+++ b/htdocs/core/lib/functions.lib.php
@@ -11374,8 +11374,10 @@ function dolGetButtonAction($label, $text = '', $actionType = 'default', $url =
 
 	// If $url is an array, we must build a dropdown button
 	if (is_array($url)) {
+		$out = '';
+
 		if (count($url) > 1) {
-			$out = '<div class="dropdown inline-block dropdown-holder">';
+			$out .= '<div class="dropdown inline-block dropdown-holder">';
 			$out .= '<a style="margin-right: auto;" class="dropdown-toggle classfortooltip butAction'.($userRight ? '' : 'Refused').'" title="'.dol_escape_htmltag($label).'" data-toggle="dropdown">'.($text ? $text : $label).'</a>';
 			$out .= '<div class="dropdown-content">';
 			foreach ($url as $subbutton) {