Cannot Change Theme in Discourse — Nothing Works

[Moin]

There is also a site setting for the banner: Enable welcome banner.
It was added recently. That’s why most themes won’t show it in the screenshots.

Bringing popular features to Discourse: Header search, welcome banner, and category icons / emoji

We have added several new features to Discourse based on popular theme components to make it easier to customize the design of your community. In this topic, we’ll share more about these new core features, how to use them, and provide information about they compare to the theme components that inspired them. Header search The header search feature moves search from the magnifying glass in the top right corner to a more prominent input field in the site header. [Header search] When more heade…