Try signing in the user after user confirmation is correct and redirect to...

Try signing in the user after user confirmation is correct and redirect to dashboard, otherwise redirect to signin page

app/controllers/confirmations_controller.rb

+class ConfirmationsController < Devise::ConfirmationsController
+
+  protected
+
+  def after_confirmation_path_for(resource_name, resource)
+    if signed_in?(resource_name)
+      signed_in_root_path(resource)
+    else
+      sign_in(resource)
+      if signed_in?(resource_name)
+        signed_in_root_path(resource)
+      else
+        new_session_path(resource_name)
+      end
+    end
+  end
+end

config/routes.rb

@@ -170,7 +170,7 @@ Gitlab::Application.routes.draw do
 
   resources :projects, constraints: { id: /[^\/]+/ }, only: [:new, :create]
 
-  devise_for :users, controllers: { omniauth_callbacks: :omniauth_callbacks, registrations: :registrations , passwords: :passwords, sessions: :sessions }
+  devise_for :users, controllers: { omniauth_callbacks: :omniauth_callbacks, registrations: :registrations , passwords: :passwords, sessions: :sessions, confirmations: :confirmations }
 
   devise_scope :user do
     get "/users/auth/:provider/omniauth_error" => "omniauth_callbacks#omniauth_error", as: :omniauth_error