## Pleroma.Emails.Mailer
* `adapter`: one of the mail adapters listed in [Swoosh readme](https://github.com/swoosh/swoosh#adapters), or `Swoosh.Adapters.Local` for in-memory mailbox.
* `api_key` / `password` and / or other adapter-specific settings, per the above documentation.
+* `enabled`: Allows enable/disable send emails. Default: `false`.
An example for Sendgrid adapter:
* `skip_thread_containment`: Skip filter out broken threads. The default is `false`.
* `limit_to_local_content`: Limit unauthenticated users to search for local statutes and users only. Possible values: `:unauthenticated`, `:all` and `false`. The default is `:unauthenticated`.
* `dynamic_configuration`: Allow transferring configuration to DB with the subsequent customization from Admin api.
+* `external_user_synchronization`: Following/followers counters synchronization settings.
+ * `enabled`: Enables synchronization
+ * `interval`: Interval between synchronization.
+ * `max_retries`: Max rettries for host. After exceeding the limit, the check will not be carried out for users from this host.
+ * `limit`: Users batch size for processing in one time.
+
## :logger