Using the default worker count of 1 leads to hangs when using SMTP, as `send_group_invitation_mail` at [canaille/core/endpoints/groups.py:285](https://gitlab.com/yaal/canaille/-/blob/0.2.3/canaille/core/endpoints/groups.py?ref_type=heads#L285) will trigger LOGO generation in [canaille/app/mails.py:28](https://gitlab.com/yaal/canaille/-/blob/0.2.3/canaille/app/mails.py?ref_type=heads#L28), which by default will attempt to fetch from itself. When using `dramatiq_eager_broker:EagerBroker` this will wait forever. The `urllib.urlopen` should have a timeout added, for example `timeout=5`. To avoid a restart being necessary, this might be relevant for more places as well. Setting the workers up (`CANAILLE_HYPERCORN__WORKERS=2 `) does not seem to help the behavior, but instead makes it erratic. Only workaround I have found is to set `LOGO = ""` to avoid this circular loop. But this is not a perfect solution.