Detected a unquoted template variable as an attribute. If unquoted, a malicious actor could inject custom JavaScript handlers. To fix this, add quotes around the template expression, like this: "{{ expr }}".
<img id="about-card-picture" src="{{ "/images/LOGO_UFCG.jpg" }}{{ if in . "//www.gravatar.com/avatar/" }}?s=110{{ end }}" alt="{{ i18n "global.author_picture" }}" />