Hi there,
Apologies that it’s taken so long to get a proper answer to this.
The way the portfolio works is, that the category select is used to pull in items from each of the selected categories. The reason that category shows up is because the filters show for all categories that have items visible on the page. I can understand why you’d want to hide that category, but it’s not really technically viable to not have something that wouldn’t show that category.
The best thing I can suggest is to add this custom css, and it will hide that filter option:
ul.portfolio-filter-tabs li a.homepage-portfolio-section-1 {
display: none!important;
}
Hope that helps.
– Ed