I can only assume that you have a group field called “bakgrund” and “del1” is a wysiwyg field sub field of this group.
getting the field should format the wysiwyg sub fields
I am lost as to why you are doing this
$infostring1 = html_entity_decode($background['del1']);
$infostring1 = preg_replace("/\s/",'',$infostring1);
$infostring1 = htmlentities($infostring1);
as it is removing all of the html formatting applied to the wysiwyg field.
Why are you not just using echo $background['del1'];