String passed to the T function in inline_template not accessible for translation For a custom field I have a formatter:

  public function viewElements(FieldItemListInterface $items, $langcode) {
    $elements = [];
    foreach ($items as $delta =&gt; $item) {
      $value = unserialize($item-&gt;value);
      $elements[$delta] = [
        '#type' =&gt; 'inline_template',
        '#template' =&gt; "{{ 'translate_me'|t }} {% for key,value in info %}  {{ key|t }}  : {{ value }} &lt;br/&gt; {% endfor %}",
        '#context' =&gt; ['info' =&gt; $value],
      ];
    }
    return $elements;
  }


I tried to search for the string "translate_me" on admin/config/regional/translate to translate it but cannot find it. I did clear the cache, run the cron, ensure the module the define the string has a version, and viewed the node in the target language. but to no avail. What am I missing? 

Thank
This was caused by the configuration for language detection and selection configuration at admin/config/regional/language/detection. 

For the t() function to work, the language detection and selection for the user interface must be set to "Language from the URL (Path prefix or domain)". There is an issue on drupal.org that may address this one.