Release of version 2.0.3 - Add an experimental "Reference block" plugin - what is it?

Hello, dear developers and colleagues!

The following message appeared in the release of version 2.0.3:

New Features
  • [undefined]
    • Add an experimental “Reference block” plugin, which allows reusing existing blocks by referencing or copying. (#7584) by @gchust

Can you tell me what this feature is and where it can be configured? Is it possible to test it?

Please refer to

Oh, do you mean "Reference Template Block "? If so, I have studied this feature and use it in my work.

I thought it was some kind of new feature that offers something new in application development. Or am I mistaken?