{{ if and .Params.author .Params.author_link }}
<a href="{{ .Params.author_link }}" target="_blank">
    <span class="fa fa-user mr-2"></span>{{ .Params.author }}
</a>
{{ else if and .Params.author (not .Params.author_link) }}
<span class="fa fa-user mr-1"></span>{{ .Params.author }}
{{ end }}