fontawesome-8.x-2.x-dev/fontawesome.services.yml

services:
  fontawesome.font_awesome_manager:
    class: Drupal\fontawesome\FontAwesomeManager
    arguments: ['@cache.font_awesome', '@module_handler', '@theme_handler', '@file_system', '@extension.list.module']
  cache.font_awesome:
    class: Drupal\Core\Cache\CacheBackendInterface
    tags:
      - { name: cache.bin }
    factory: cache_factory:get
    arguments: [font_awesome]