herokuでのfacebook認証

Question

###前提・実現したいこと
omniauthでfacebook認証を実装しており、localでは問題なく動いたのですが、herokuにデプロイしてからうまく動きません。アドバイスいただけますでしょうか。

###発生している問題・エラーメッセージ

stripe実装時にもこの画面が出たので、facebook側ではなくheroku側のエラーと思います。またこのエラーが出る前に、facebook側で
Can't Load URL: The domain of this URL isn't included in the app's domains. To be able to load this URL, add all domains and subdomains of your app to the App Domains field in your app settings.
というエラーが出ていましたが、それはfacebookにherokuのurlを登録して解決しました。

###該当のソースコード
config/initializers/devise.rb

config.omniauth :facebook, ENV["facebook_app_id"], ENV["facebook_app_secret"], scope: 'email', info_fields: 'email,name', secure_image_url: true

app/models/user.rb

  def self.from_omniauth(auth)
  where(provider: auth.provider, uid: auth.uid).first_or_create do |user|
    user.email = auth.info.email
    user.password = Devise.friendly_token[0,20]
    user.name = auth.info.name   # assuming the user model has a name
    user.image = "http://graph.facebook.com/#{auth.uid}/picture?type=large" # assuming the user model has an image
    # If you are using confirmable and the provider(s) you use validate emails,
    # uncomment the line below to skip the confirmation emails.
    # user.skip_confirmation!
    end
  end

controllers/users/omniauth_callback_controller.rb

class Users::OmniauthCallbacksController < Devise::OmniauthCallbacksController
  def facebook
    # You need to implement the method below in your model (e.g. app/models/user.rb)
    @user = User.from_omniauth(request.env["omniauth.auth"])

    if @user.persisted?
      sign_in_and_redirect @user, :event => :authentication #this will throw if @user is not activated
      set_flash_message(:notice, :success, :kind => "Facebook") if is_navigational_format?
    else
      session["devise.facebook_data"] = request.env["omniauth.auth"]
      redirect_to new_user_registration_url
    end
  end

  def failure
    redirect_to root_path
  end
end

###試したこと
色々調べてみましたが、情報が2011-13年と古いものが多かったり、すでに実行済みのものであったり、という状況です。figaro heroku:set -e productionをしているのでapp idとsecretはちゃんとherokuに入っているはずです。

###補足情報(言語/FW/ツール等のバージョンなど)
herokuのlogを晒せというアドバイスが他のサイトにあったので、晒します。

2017-07-17T15:33:54.234171+00:00 app[web.1]: Started GET "/users/auth/facebook/callback?code=AQCoKbzr4 ＜中略＞ 00703" for 150.116.22.144 at 2017-07-17 15:33:54 +0000
2017-07-17T15:33:54.236011+00:00 app[web.1]: I, [2017-07-17T15:33:54.235951 #4]  INFO -- omniauth: (facebook) Callback phase initiated.
2017-07-17T15:33:54.360053+00:00 app[web.1]: Processing by Users::OmniauthCallbacksController#facebook as HTML
2017-07-17T15:33:54.360097+00:00 app[web.1]:   Parameters: {"code"=>"AQCoKbzr4nv6c7BEpM ＜中略＞ 86c27a00703"}
2017-07-17T15:33:54.371557+00:00 app[web.1]:   User Load (1.8ms)  SELECT  "users".* FROM "users" WHERE "users"."provider" = $1 AND "users"."uid" = $2  ORDER BY "users"."id" ASC LIMIT 1  [["provider", "facebook"], ["uid", "102081518247"]]
2017-07-17T15:33:54.581790+00:00 heroku[router]: at=info method=GET path="/users/auth/facebook/callback?code=AQCoK ＜中略＞ a00703" host=xxxxxxx-xxxx-xxxxx.herokuapp.com request_id=93945-1199-417e-8d98-ede264cb fwd="150.116.22.144" dyno=web.1 connect=1ms service=350ms status=500 bytes=1754 protocol=https
2017-07-17T15:33:54.578410+00:00 app[web.1]: Completed 500 Internal Server Error in 218ms (ActiveRecord: 3.0ms)
2017-07-17T15:33:54.579175+00:00 app[web.1]: 
2017-07-17T15:33:54.579178+00:00 app[web.1]: RuntimeError (redirection forbidden: http://graph.facebook.com/102087018247/picture?type=large -> https://scontent.xx.fbcdn.net/v/t1.0-1/p200x200/13064_10202475740292_410664266178542_n.jpg?oh=ef118e9d947604c9c7055a92e2&oe=5A02F8B4):
2017-07-17T15:33:54.579178+00:00 app[web.1]:   app/models/user.rb:18:in `block in from_omniauth'
2017-07-17T15:33:54.579179+00:00 app[web.1]:   app/models/user.rb:14:in `from_omniauth'
2017-07-17T15:33:54.579180+00:00 app[web.1]:   app/controllers/users/omniauth_callbacks_controller.rb:4:in `facebook'
2017-07-17T15:33:54.579180+00:00 app[web.1]: 
2017-07-17T15:33:54.579181+00:00 app[web.1]:

Answer 1

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