zammad/app/views/knowledge_base/public/_breadcrumb.html.erb

<nav class="breadcrumbs">
  <div class="container">
    <% ([knowledge_base] + objects).each do |object| %>
      <%= link_to custom_path_if_needed(breadcrumb_path_for(object), knowledge_base), class: :breadcrumb do %>
        <%= icon_for_object(object, knowledge_base.iconset) %>

        <span>
          <%= breadcrumb_text_for(object) %>
        </span>
      <% end %>
    <% end %>
  </div>
</nav>