Overriding `default_scope` in `has_many` `through` association.

website.rb

class Website < ActiveRecord::Base
  default_scope { where.not(is_private: true) }
end

website_screenshot.rb

class WebsiteScreenshot < ActiveRecord::Base
  Website.unscope(where: :is_private) do
    belongs_to :website
    has_many :website_follows, through: :website
  end
end