mulitLine for Notifications is not working

[StefanFl]

What you were expecting:

let message = "Created: 0\nDuplicates: 3\nUnsuccessful: 0";
notify(message, { type: "success", autoHideDuration: 10000, multiLine: true });

The notification should be displayed with 3 lines

What happened instead:

The notification has only 1 line:

Steps to reproduce:

see above
Environment

• React-admin version: 4.2.7
• Last version that did not exhibit the issue (if applicable): n/a
• React version: 18.2.0
• Browser: Firefox