How do I set an empty link title in a menu item?
No need to resort to "dirty CSS tricks", you can just use clean CSS:

a.class {
  display: inline-block; // Or block if it makes more sense for your layout.
  text-indent: -9999em;
}


This is the correct way to handle it, as you can include proper text as your link (e.g. "Home"), so you're not alienating users with screen readers, etc.