Error message looks like it's using the field "name" attribute and not the Label. I would expect "navigation-group" to read "Navigation Group" which currently feels broken. Also, a numbered list with a single item feels broken. Would a bullet list be more appropriate? Are errors always specifically ordered?
The label thing might be a limitation. There is potential for, when rendering errors, to do a lookup to find the field label. Might need to look into it.
Error message looks like it's using the field "name" attribute and not the Label. I would expect "navigation-group" to read "Navigation Group" which currently feels broken. Also, a numbered list with a single item feels broken. Would a bullet list be more appropriate? Are errors always specifically ordered?