Change displayed clue of HTML page title

I have a custom list called Customers which contains, columns First Name, Last Name and Full Name. Full Name is a calculated column which concatenates the first and last name values.

Currently, when you click on any customer in the list to view the item, the HTML title for the page is Customers - {Last Name}. However, what I would like to do, is to change it to Customers - {Full Name}.

How do I change the HTML title for the Default Display Form for the Customers list only?