Hi Geert
In your InlineIcon icon modules default.php (../modules/mod_j51inlineicons/tmpl/default.php - line63 locate the following...
echo '<a href="'.$item->j51_iconurl.'" class="j51_inlineicon" data-balloon="'.$item->j51_icontitle.'" data-balloon-pos="up"><i class="'.$item->j51_iconclass.'" style="color:'.$item->j51_iconcolor.'"></i></a>';
And change to...
echo '<a href="'.$item->j51_iconurl.'" target="_blank" class="j51_inlineicon" data-balloon="'.$item->j51_icontitle.'" data-balloon-pos="up"><i class="'.$item->j51_iconclass.'" style="color:'.$item->j51_iconcolor.'"></i></a>';
Ciarán