This extension is considered obsolete since Flux (the engine used by this extension) now provides a similar but better method of using templates as content element types. The most recent release of this extension, version 6.0, should only be used if you must upgrade an existing site and must avoid migrating templates (at the current time of writing this, automatic migration is not possible).

For new projects you can simply skip installing fluidcontent and use the exact same registerProviderExtensionKey function to register your templates. Flux detects that fluidcontent isn't installed and takes over.

Please note the following key differences between fluidcontent and flux in how they register templates:

• fluidcontent uses a wrapping fluidcontent_content CType which behaves like plugins in that it has a sub-type where you select the Fluid template to be used as content template.
• flux directly registers your template as a new, unique CType which behaves like a true content type (but still allows you to use a ContentController)
• Without fluidcontent installed, access restrictions for allowed content types are now configured directly from the standard content types list. And subsequently you need to target the individual CTypes when configuring allowedContentTypes or deniedContentTypes in Flux grid columns and when customising the TCA/TS for your content types.

The parts that cannot be migrated (yet) are exactly those parts: converting the existing content records' type values and scanning for possible references to the converted content types (and either reporting or fixing by rewriting those cases). Apart from that the solutions are compatible in that they consume the exact same type of templates with the same configuration.