No route matches [HEAD] "/auth/auth0"... but GET works

I am using Ruby on Rails 5.2, with the omniauth and omniauth-auth0 gems, for a classic webpage.
Further I spider my page with wget to scan for obvious errors.

The call
wget -S --spider http://localhost:3000/auth/auth0
results in
No route matches [HEAD] "/auth/auth0"

The GET call just works as expected: wget -S http://localhost:3000/auth/auth0, and shows omniauth: (auth0) Request phase initiated.

This is the same both on

gem 'omniauth', '~> 1.6.1'
gem 'omniauth-auth0', '~> 2.0.0'

as on

gem 'omniauth-auth0', '~> 2.2.0'

I am not entirely sure if this is for some reason intended, caused by my setup, by omniauth, or by omniauth-auth0.

How can HEAD requests be enabled?

Greetings, Kjell