How to display the breadcrumb trail in a Bootstrap template

198/5000 I have a site with Drupal 8 and Bootstrap 3.3.6

I want to display the breadcrumbs on the navigation bar.

I created a region “Breadcrumb” in my theme. I do not know if this is necessary. And I activated the “Breadcrumb” block in this region.

The problem is that the wire is not displayed.

Here is my file page.html.twig :

{# /**  * @file  * Default theme implementation to display a single page.  *  * The doctype, html, head and body tags are not in this template. Instead they  * can be found in the html.html.twig template in this directory.  *  * Available variables:  *  * General utility variables:  * - base_path: The base URL path of the Drupal installation. Will usually be  *   "/" unless you have installed Drupal in a sub-directory.  * - is_front: A flag indicating if the current page is the front page.  * - logged_in: A flag indicating if the user is registered and signed in.  * - is_admin: A flag indicating if the user has permission to access  *   administration pages.  *  * Site identity:  * - front_page: The URL of the front page. Use this instead of base_path when  *   linking to the front page. This includes the language domain or prefix.  *  * Navigation:  * - breadcrumb: The breadcrumb trail for the current page.  *  * Page content (in order of occurrence in the default page.html.twig):  * - title_prefix: Additional output populated by modules, intended to be  *   displayed in front of the main title tag that appears in the template.  * - title: The page title, for use in the actual content.  * - title_suffix: Additional output populated by modules, intended to be  *   displayed after the main title tag that appears in the template.  * - messages: Status and error messages. Should be displayed prominently.  * - tabs: Tabs linking to any sub-pages beneath the current page (e.g., the  *   view and edit tabs when displaying a node).  * - action_links: Actions local to the page, such as "Add menu" on the menu  *   administration interface.  * - node: Fully loaded node, if there is an automatically-loaded node  *   associated with the page and the node ID is the second argument in the  *   page's path (e.g. node/12345 and node/12345/revisions, but not  *   comment/reply/12345).  *  * Regions:  * - page.header: Items for the header region.  * - page.navigation: Items for the navigation region.  * - page.navigation_collapsible: Items for the navigation (collapsible) region.  * - page.highlighted: Items for the highlighted content region.  * - page.help: Dynamic help text, mostly for admin pages.  * - page.content: The main content of the current page.  * - page.sidebar_first: Items for the first sidebar.  * - page.sidebar_second: Items for the second sidebar.  * - page.footer: Items for the footer region.  *  * @ingroup templates  *  * @see template_preprocess_page()  * @see html.html.twig  */ #}  <div id="bg-animation"> </div>  {# Navigation (collapsible first) #} {% if page.navigation_collapsible_first %}   <div id="navbar-collapse-first" class="navbar-collapse-first collapse width navbar-collapse-first-fixed-top">     {{ page.navigation_collapsible_first }}   </div> {% endif %}  {% set container = theme.settings.fluid_container ? 'container-fluid' : 'container' %} {# Navbar #} {% if page.navigation_menu_first or page.navigation_indicator_first or page.navigation_logo or page.navigation_indicator_second or page.navigation_menu_second or page.navigation_collapsible_first or page.navigation_collapsible_second %}   {% block navbar %}     {%       set navbar_classes = [         'navbar',         theme.settings.navbar_inverse ? 'navbar-inverse' : 'navbar-default',         theme.settings.navbar_position ? 'navbar-' ~ theme.settings.navbar_position|clean_class : container,       ]     %}     <header{{ navbar_attributes.addClass(navbar_classes) }} id="navbar" role="banner">       {% if not navbar_attributes.hasClass(container) %}         <div class="{{ container }}">       {% endif %}       <div class="navbar-header">         {{ page.navigation_menu_first }}         {{ page.navigation_notification_first }}         {{ page.navigation_logo }}         {{ page.navigation_menu_second }}         {{ page.navigation_notification_second }}         {# .btn-navbar is used as the toggle for collapsed navbar content #}       </div>        {% if not navbar_attributes.hasClass(container) %}         </div>       {% endif %}     </header>   {% endblock %} {% endif %}  {# Navigation (collapsible second) #} {% if page.navigation_collapsible_second %}   <div id="navbar-collapse-second" class="navbar-collapse-second collapse width navbar-collapse-second-fixed-top">     {{ page.navigation_collapsible_second }}   </div> {% endif %}  {# Breadcrumbs #} {% if breadcrumb %}   {% block breadcrumb %}     {{ breadcrumb }}   {% endblock %} {% endif %}  {# Main #} {% block main %}   <div role="main" class="main-container {{ container }} js-quickedit-main-content">     <div class="row">        {# Header #}       {% if page.header %}         {% block header %}           <div class="col-xs-12 col-sm-12 col-md-12 col-lg-12" role="heading">             {{ page.header }}           </div>         {% endblock %}       {% endif %}        {# Sidebar First #}       {% if page.sidebar_first %}         {% block sidebar_first %}           <aside class="col-xs-12 col-sm-12 col-md-3 col-lg-3 sidebar-first" role="complementary">             {{ page.sidebar_first }}           </aside>         {% endblock %}       {% endif %}        {# Content #}       {%         set content_classes = [           page.sidebar_first and page.sidebar_second ? 'col-xs-12 col-sm-12 col-md-6 col-lg-6',           page.sidebar_first and page.sidebar_second is empty ? 'col-xs-12 col-sm-12 col-md-9 col-lg-9',           page.sidebar_second and page.sidebar_first is empty ? 'col-xs-12 col-sm-12 col-md-9 col-lg-9',           page.sidebar_first is empty and page.sidebar_second is empty ? 'col-xs-12 col-sm-12 col-md-12 col-lg-12'         ]       %}       <section{{ content_attributes.addClass(content_classes) }}>         {# Highlighted #}         {% if page.highlighted %}           {% block highlighted %}             <div class="highlighted">{{ page.highlighted }}</div>           {% endblock %}         {% endif %}          {# Action Links #}         {% if action_links %}           {% block action_links %}             <ul class="action-links">{{ action_links }}</ul>           {% endblock %}         {% endif %}          {# Help #}         {% if page.help %}           {% block help %}             {{ page.help }}           {% endblock %}         {% endif %}          {# Content #}         {% block content %}           <a id="main-content"></a>           {{ page.content }}         {% endblock %}       </section>        {# Sidebar Second #}       {% if page.sidebar_second %}         {% block sidebar_second %}           <aside class="col-xs-12 col-sm-12 col-md-3 col-lg-3 sidebar-second" role="complementary">             {{ page.sidebar_second }}           </aside>         {% endblock %}       {% endif %}     </div>   </div> {% endblock %}  {% if page.footer %}   {% block footer %}     <footer class="footer {{ container }}" role="contentinfo">       {{ page.footer }}     </footer>   {% endblock %} {% endif %} 

Here is my file bootstrap_subtheme_front_office.info.yml :

core: 8.x type: theme base theme: bootstrap  name: 'Bootstrap Sub-Theme Front Office' description: 'Uses the Bootstrap framework LESS source files and must be compiled (not for beginners).' package: 'Bootstrap'  regions:   navigation_collapsible_first: 'Navigation (Collapsible first)'   navigation_menu_first: 'Navigation (Menu first)'   navigation_notification_first: 'Navigation (Notification first)'   navigation_logo: 'Navigation (Logo)'   navigation_notification_second: 'Navigation (Notification second)'   navigation_menu_second: 'Navigation (Menu second)'   navigation_collapsible_second: 'Navigation (Collapsible second)'   breadcrumb: 'Breadcrumb'   header: 'Top Bar'   sidebar_first: 'Primary'   highlighted: 'Highlighted'   help: 'Help'   content: 'Content'   sidebar_second: 'Secondary'   footer: 'Footer'  libraries:   - bootstrap_subtheme_front_office/global-styling   - bootstrap_subtheme_front_office/bootstrap