def compatibly_redirect_back(request_params = {})
        # :only-rails5+:
        if Rails::VERSION::MAJOR >= 5
          redirect_back fallback_location: { action: :index }, **request_params
        # :only-rails5+:
        # :except-rails5+:
        elsif request.referer
          redirect_to :back, **request_params
        else
          redirect_to action: :index, **request_params
        end
        # :except-rails5+:
        true
      end
def compatibly_redirect_back(request_params = {})
        # :only-rails5+:
        if Rails::VERSION::MAJOR >= 5
          redirect_back fallback_location: { action: :index }, **request_params
        # :only-rails5+:
        # :except-rails5+:
        elsif request.referer
          redirect_to :back, **request_params
        else
          redirect_to action: :index, **request_params
        end
        # :except-rails5+:
        true
      end
Redirect to back.
 @api protected
 @return [Boolean] True