Can't enable anonymous sign ins locally

I tried to enable anonymous sign ins according to the docs (1, 2):

[auth]
enable_anonymous_sign_ins = true

[auth]
enable_anonymous_sign_ins = true

but supabase logs this when I run

supabase start

supabase start

Unknown config fields: [auth.enable_anonymous_sign_ins]

Unknown config fields: [auth.enable_anonymous_sign_ins]