Can't get social.html from minima theme to work

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1

For demonstration purposes I’ve created a brand new project with jekyll new .

It creates a new project with the minima theme.

in the includes/footer.html there is:

{%- include social.html -%}

in the social.html there is:

{%- if site.github_username -%}<li><a href="https://github.com/{{ site.github_username| cgi_escape | escape }}"><svg class="svg-icon"><use xlink:href="{{ '/assets/minima-social-icons.svg#github' | relative_url }}"></use></svg> <span class="username">{{ site.github_username| escape }}</span></a></li>{%- endif -%}
{%- if site.twitter_username -%}<li><a href="https://www.twitter.com/{{ site.twitter_username| cgi_escape | escape }}"><svg class="svg-icon"><use xlink:href="{{ '/assets/minima-social-icons.svg#twitter' | relative_url }}"></use></svg> <span class="username">{{ site.twitter_username| escape }}</span></a></li>{%- endif -%}

In the _config.yml there is:

twitter_username: jekyllrb
github_username:  jekyll

However, the github and twitter links don’t show up in the footer when using bundle exec jekyll serve