User Concern is removing Devise settings

When I include
include DeviseTokenAuth::Concerns::User

below my devise settings
devise :database_authenticatable, :registerable,
:recoverable, :rememberable, :trackable, :validatable, :omniauthable, :omniauth_providers => [:facebook, :google_oauth2]
include DeviseTokenAuth::Concerns::User

I am getting the following error
Mapping omniauth_callbacks on a resource that is not omniauthable (ArgumentError) Please add devise :omniauthable to the User model

I looked at the source code for
https://github.com/lynndylanhurley/devise_token_auth/blob/master/app/models/devise_token_auth/concerns/user.rb

I think the problem might be with

Hack to check if devise is already enabled

unless self.method_defined?(:devise_modules)
  devise :database_authenticatable, :registerable,
      :recoverable, :trackable, :validatable, :confirmable
else
  self.devise_modules.delete(:omniauthable)
end

I am using
Rails 4.2
devise (3.5.1)
devise_token_auth (0.1.31)
omniauth (1.2.2)
omniauth-facebook (2.0.1)
omniauth-google-oauth2 (0.2.6)
omniauth-oauth2 (1.3.1)

Start with app/models/devise_token_auth/concerns/user.rb, especially the devise_modules handling shown in the issue, and reproduce the error using the listed Rails, Devise, and devise_token_auth versions. Trace why an existing :omniauthable setting is removed, then verify that the User model retains the configured OmniAuth support without breaking the other Devise modules.