### Begin of the deletion Before filing a report

_Before you file a report, please ensure you are running the latest version of OpenProject and_ 
_have searched for similar bug reports._

###End of the deletion Steps to reproduce

Begin of the insertionBootEnd of the insertion Begin of the deletion First startingEnd of the deletion OpenProject Begin of the insertionwithEnd of the insertion Begin of the deletion while pinningEnd of the deletion the Begin of the insertionENV for theEnd of the insertion Begin of the deletion `mail_from`End of the deletion setting Begin of the insertion`mail_from` setEnd of the insertion to Begin of the insertionsome value. Without this itEnd of the insertion Begin of the deletion a given value (thisEnd of the deletion works Begin of the insertionfine. E.g. start like this:End of the insertion Begin of the deletion fine when you don't).End of the deletion

```bash
docker run --rm -e OPENPROJECT_HTTPS=false -e OPENPROJECT_HOST__NAME=localhost:8080 -e OPENPROJECT_MAIL__FROM=notifications@openproject.com -p 8080:80 -it openproject/openproject:17.0.1
```

1. After starting OpenProject as shown above, navigate to Administration -> Email & notifications -> Email notifications

2. Try updating the email footer


### What is the buggy behavior?

* error: "Emission email address is not a valid email address."


### What is the expected behavior?

* The update should be successful


### Environment information

**OpenProject installation type**

* [x] Hosted cloud edition
* [x] Packaged installation
* [x] Docker All-in-one container
* [x] Docker-compose installation

**OpenProject version**

17.0.1