discourse/app/assets/javascripts/admin/templates/modal/admin_incoming_email.hbs

<div class="control-group">
  <label>{{i18n "admin.email.incoming_emails.modal.error"}}</label>
  <div class="controls">
    <p>{{model.error}}</p>
    {{#if model.error_description}}
      <p class="error-description">{{model.error_description}}</p>
    {{/if}}
  </div>
</div>

<hr>

<div class="control-group">
  <label>{{i18n "admin.email.incoming_emails.modal.headers"}}</label>
  <div class="controls">
    {{textarea value=model.headers wrap="off"}}
  </div>
</div>

<div class="control-group">
  <label>{{i18n "admin.email.incoming_emails.modal.subject"}}</label>
  <div class="controls">
    {{model.subject}}
  </div>
</div>

<div class="control-group">
  <label>{{i18n "admin.email.incoming_emails.modal.body"}}</label>
  <div class="controls">
    {{textarea value=model.body}}
  </div>
</div>

{{#if model.rejection_message}}

  <hr>

  <div class="control-group">
    <label>{{i18n "admin.email.incoming_emails.modal.rejection_message"}}</label>
    <div class="controls">
      {{textarea value=model.rejection_message}}
    </div>
  </div>

{{/if}}