Translate module strings In a custom D8 theme, we have some strings in twig using |t filter and in php using $this-t() funtion.

example :


{{'More Headlines'|t}}



$this->t('replies') 


These strings are not listed in /admin/config/regional/translate. What's the right way to translate it via the administration interface like it was possible with D7?
You just need to first visit the page rendering the string you want to translate while using any other language.

Drupal only adds this string to the database once it has been rendered once, and you will be able to see it in the /admin/config/regional/translate page.