bt_forum-8.x-1.x-dev/bt_forum.services.yml

services:
#  bt_forum.overrider:
#    class: \Drupal\bt_forum\Config\ConfigForumOverride
#    arguments: ['@config.storage', '@event_dispatcher', '@config.typed']
#    tags:
#      - {name: config.factory.override, priority: 25}
  bt_forum.breadcrumbs:
    class: Drupal\bt_forum\Breadcrumb\ForumBreadcrumbBuilder
    arguments: ['@config.factory']
    tags:
      - { name: breadcrumb_builder, priority: 1100 }