shinyswatch.theme.pulse() and primary button

Theme Pulse is advertised as being purple "oriented"; but the first thing I tried did not worrk.

When I add a primary button, it does not show in purple; instead, it shows in the (shiny?) default color? I mean, I can read ui.input_task_button description where it says that type='primary'means the default color....but it should be the default of the current theme, not the defatul color of the default theme.

When I swittch to one of the other choices like 'success' or 'danger', the button is colored accordingly...it just does not seem to work for 'primary'