Front matter variables not included in public

support
1

When I use the hugo command to build the public folder, the custom content front matter variables are not included.

ex content/about/_index.md

title : "About"
type : "about"
layout : "single"
aliases:
    - /about/home
jumboHeading : "Hello world"
foo: "Bar"

ex: layouts/about/single.html

{{ define "main" }}
{{ partial "aboutHero" . }}
{{ partial "values" . }}
{{ partial "staff" . }}
{{ partial "advisor" . }}
{{ partial "specialization" . }}
{{ partial "consultation" . }}
{{ partial "footer" . }}
{{ end }}

example of partial:
<div>{{ .Params.foo }}</div>

2

go with

<div>{{ $.Params.foo }}</div>