{% load i18n %}
<a href="#c0" class="comment-cancel-reply-link">cancel reply</a>
<span class="comment-waiting" id="comment-waiting-{{ target_object.pk }}" style="display: none;">
  <img src="{{ STATIC_URL }}fluent_comments/img/ajax-wait.gif" alt="" class="ajax-loader" />{% trans "Please wait . . ." %}
</span>
<span class="comment-added-message" id="comment-added-message-{{ target_object.pk }}" style="display: none;">{% trans "Your comment has been posted!" %}</span>
<div class="comment-moderated-message" id="comment-moderated-message-{{ target_object.pk }}" style="display: none;">{% trans "Your comment has been posted, it will be visible for other users after approval." %}</div>

{% load i18n %}
<a href="#c0" class="comment-cancel-reply-link">{% trans "cancel reply" %}</a>
<span class="comment-waiting" id="comment-waiting-{{ target_object.pk }}" style="display: none;">
  <img src="{{ STATIC_URL }}fluent_comments/img/ajax-wait.gif" alt="" class="ajax-loader" />{% trans "Please wait . . ." %}
</span>
<span class="comment-added-message" id="comment-added-message-{{ target_object.pk }}" style="display: none;">{% trans "Your comment has been posted!" %}</span>
<div class="comment-moderated-message" id="comment-moderated-message-{{ target_object.pk }}" style="display: none;">{% trans "Your comment has been posted, it will be visible for other users after approval." %}</div>

Add forgotten trans tag to "cancel reply"
Add forgotten trans tag to "cancel reply"