Copyright &copy; {{ site.time | date: "%Y" }} {{ site.author }}

Copyright &copy; {{ site.time | date: "%Y" }}
{% if site.author %}
    {{ site.author }}
{% else %}
    {{ site.title }}
{% endif %}

Use site.title in the copyright notice if site.author is not available.
Use site.title in the copyright notice if site.author is not available.
