diff --git a/htdocs/core/boxes/modules_boxes.php b/htdocs/core/boxes/modules_boxes.php
index d1d05ec28a8..808af6a68b9 100644
--- a/htdocs/core/boxes/modules_boxes.php
+++ b/htdocs/core/boxes/modules_boxes.php
@@ -287,7 +287,10 @@ class ModeleBoxes    // Can't be abtract as it is instantiated to build "empty"
                             // Url
                             if (! empty($contents[$i][$j]['url']) && empty($contents[$i][$j]['logo']))
                             {
-                                $out.= '<a href="'.$contents[$i][$j]['url'].'" title="'.dol_escape_htmltag($langs->trans("Show").' '.$tooltip, 1).'" class="classfortooltip"';
+                                $out.= '<a href="'.$contents[$i][$j]['url'].'"';
+                                if (!empty($tooltip)) {
+                                    $out .= ' title="'.dol_escape_htmltag($langs->trans("Show").' '.$tooltip, 1).'" class="classfortooltip"';
+                                }
                                 //$out.= ' alt="'.$textwithnotags.'"';      // Pas de alt sur un "<a href>"
                                 $out.= isset($contents[$i][$j]['target'])?' target="'.$contents[$i][$j]['target'].'"':'';
                                 $out.= '>';