Bootstrap navbar not expanding in bootstrap-v5 theme

Hi, I am trying to work out why when adding a navbar to a view using the bootstrap-v5 theme the menu button does not expand the menu. I have set up a test site with latest versions of CI, GC and bootstrap theme here:

test_kotoba_co_uk (replace _ with .)

codeigniter: 4.1.5
grocery crud: 2.0.1
bootstrap-V5-theme: 1.5.3

This is normally when the bootstrap js is not included correctly. Do I need to include anything else in the html?