Custom HTML on Groups page

[smrtey]

Or if you want something fancier try

Versatile Banner

Summary Versatile Banner adds a customizable banner to your site. Preview Preview on theme-creator.discourse.org Repository Link https://github.com/discourse/discourse-versatile-banner New to Discourse Themes? Beginner’s guide to using Discourse Themes Install this theme component This theme component is an evolution of previous banner efforts. The goal is to provide more ease and flexibility through the use of them…