Multilanguage concat strings in frontmatter

In Grav docs there's a basic example of the form config and there's this line:

subject: "[Feedback] {{ form.value.name|e }}"

I've searched and YAML doesn't support string concatenation. Also I somehow doubt Grav has the ability to parse multilingual placeholder only in part of the strings.

Is there any way to make the Feedback word multilingual? Or maybe some workaround?