# expected behavior to access `ah` with either string or symbol keys
ah= OmniAuth::AuthHash.new(provider: :idcat_mobil)
ah.method(:slice)
=> #<Method: OmniAuth::AuthHash(Hashie::Mash)#slice(*keys)
ah.slice :provider
=> {"provider"=>:idcat_mobil}

# only accepts string keys
ah= OmniAuth::AuthHash.new(provider: :idcat_mobil)
ah.method(:slice).inspect
=> "#<Method: OmniAuth::AuthHash(Hash)#slice(*)>"
ah.slice(:provider, :uid, :info)
=> {}

WARN -- : [a34b1258-18e6-4d3d-9ac7-0ad4495e310d] You are setting a key that conflicts with a built-in method SnakyHash::StringKeyed#method defined in Kernel. This can cause unexpected behavior when accessing the key as a property. You can still access the key via the #[] method.
INFO -- : [a34b1258-18e6-4d3d-9ac7-0ad4495e310d] Processing by Decidim::Devise::OmniauthRegistrationsController#idcat_mobil as HTML
INFO -- : [a34b1258-18e6-4d3d-9ac7-0ad4495e310d]   Parameters: {"code"=>"[FILTERED]", "state"=>"a654797f2bfd605c46d9c3c2e1b835d94c007b86a3c68c36"}
INFO -- : [a34b1258-18e6-4d3d-9ac7-0ad4495e310d] Completed 500 Internal Server Error in 1ms (ActiveRecord: 0.0ms | Allocations: 794)
ERROR -- : [a34b1258-18e6-4d3d-9ac7-0ad4495e310d] @app.call rescued from: undefined method `with_indifferent_access' for nil:NilClass => .../decidim-core/lib/decidim/attribute_object/form.rb:82:in `hash_from'
.../decidim-core/lib/decidim/attribute_object/form.rb:72:in `from_params'
.../decidim-core/app/controllers/concerns/decidim/form_factory.rb:65:in `from_params'
.../decidim-core/app/controllers/decidim/devise/omniauth_registrations_controller.rb:18:in `create'
.../decidim-core/app/controllers/decidim/devise/omniauth_registrations_controller.rb:50:in `action_missing'
...