Contao

Yes, Contao is an established open-source PHP content management system with an active project and community. Calling it a ghost CMS because it is unsupported by its original developers is misleading, since the project has continued beyond its original creators.

Contao is a PHP-based CMS and uses the Symfony ecosystem in modern versions. It is aimed at structured websites that need reusable content types, permissions, extensions, and editorial workflows.

Contao is often chosen for structured, custom business websites where granular permissions and content modeling matter. WordPress has a much larger general-purpose plugin and theme ecosystem, while Contao is more focused on controlled site builds.

Yes, Contao supports extensions, themes, templates, and modules that extend the core system. The exact compatibility depends on the Contao major version, so extensions should be checked before upgrading or starting a project.