Encoded string in alert email subject; Setting?

Librenms: 1.58

After the last monthly update I noticed a change in the Strings:

Subject: =?us-ascii?Q?Alert_for_device_myserver_-_[myserver]Devices?= =?us-ascii?Q?up/down?=

before, it was just plain text.

My question is, if there is a setting for the encoding? Or where does it take the encoding information “us-ascii” from?

The setting Alerting-> Email Options -> “Use HTML emails” is off