Activate device email change confirmation

db/migrate/20190704133749_add_unconfirmed_email_column_to_users.rb

@@ -0,0 +1,5 @@
+class AddUnconfirmedEmailColumnToUsers < ActiveRecord::Migration[5.2]
+  def change
+    add_column :users, :unconfirmed_email, :text
+  end
+end

db/schema.rb

@@ -605,6 +605,7 @@ ActiveRecord::Schema.define(version: 2019_07_04_144304) do
     t.string "confirmation_token"
     t.datetime "confirmed_at"
     t.datetime "confirmation_sent_at"
+    t.text "unconfirmed_email"
     t.index ["confirmation_token"], name: "index_users_on_confirmation_token", unique: true
     t.index ["email"], name: "index_users_on_email", unique: true
     t.index ["reset_password_token"], name: "index_users_on_reset_password_token", unique: true