Hi Patrick,
The Group’s header’s size is set to ‘auto’ in the current version. We will add an option to jqxListBox, for the next version. At present, you can manually set the Group’s header size by using a code like this:
var source = [ {html: "<div tabIndex=0 style='padding: 1px;'><div>Title: Do the Work</div><div>Author: Steven Pressfield</div></div>", title: "Do the Work", group: "Business", groupHtml: "<div style='padding-top: 10px; padding-bottom: 10px; width: 270px; background: Red; color: Blue;'>Business</div>" },];
Best Regards,
Peter Stoev