Hi,
You'll find the code displaying the custom item fields in the checkout cart by edit the file "cart" of the view "checkout" via the menu Display>Views. Here is the code corresponding to that:
if(hikashop_level(2) && !empty($this->extraFields['item'])){
foreach($this->extraFields['item'] as $field){
$namekey = $field->field_namekey;
if(empty($row->$namekey) || !strlen($row->$namekey)) continue;
echo '<p class="hikashop_cart_item_'.$namekey.'">'.$this->fieldsClass->getFieldName($field).': '.$this->fieldsClass->show($field,$row->$namekey).'</p>';
}
}
As you can see, there is no br tag there.
So it's probably not coming from that but from some CSS of your website.