app/views/user_mailer/reconfirmation_instructions.text.erb
<%= t 'devise.mailer.reconfirmation_instructions.title' %>
===
<%= t 'devise.mailer.reconfirmation_instructions.explanation' %>
=> <%= confirmation_url(@resource, confirmation_token: @token) %>
<%= t 'devise.mailer.reconfirmation_instructions.extra' %>