Valid (while escaping the newline:
```
+ msg_json='{"text": "*ZFS scrub_finish error for test on quartz*\nZFS has detected a data error:\n\n eid: 124\n class: scrub_finish\n host: quartz\n time: \n error: \n objid: :\n pool: test\n"}'
```
Invalid (no escape):
```
+ msg_json='{"text": "*ZFS scrub_finish error for test on quartz*
ZFS has detected a data error:\n\n eid: 124\n class: scrub_finish\n host: quartz\n time: \n error: \n objid: :\n pool: test\n"}'
```
The new line gets rendered and not sent inside the JSON as intended.
```
++ curl -X POST https://discord.com/api/webhooks/{webhook.id}/{webhook.token}/slack --header 'Content-Type: application/json' --data-binary '{"text": "*ZFS scrub_finish error for test on quartz*
ZFS has detected a data error:\n\n eid: 124\n class: scrub_finish\n host: quartz\n time: \n error: \n objid: :\n pool: test\n"}'
+ msg_out='{"message": "Cannot send an empty message", "code": 50006}'
```