public/issue.html (12 lines of code) (raw):
<html>
<head>
<link rel="stylesheet" href="https://p.trellocdn.com/power-up.min.css">
</head>
<body>
<div id="content">
This feature is coming soon
<img alt="issues" src="images/issues.svg" />
Follow <a href="https://gitlab.com/gitlab-org/trello-power-up/issues/31" target="_blank" rel="noopener noreferrer" class="mod-primary mod-bottom">this GitLab issue</a> to learn more
</div>
</body>
</html>