Create the Definition app docs. I propose 2 pages:

• Module page; can be very small, mainly containing the typical installing instructions
• App page - which will be the main taks.

The app page should explain:

• The meaning of the app
  • It shows only definition items which belong to a registry
  • The displayed items may be decorated, the app shows the decorated state (to be checked e.g. with apchelintcev or just by testing it)
    • etc. pp
• How it can help a developer, why it is useful, that it will be replacement for the (JCR based) configuration app in many but not in all aspects
• etc. pp

An important note - to repeat it again:
When does it make sense to use the definition app instead of the (JCR based) configuration app, and when not.
Since we have a bunch of links to the (JCR based) configuration app, some of them also must be aligned / changed. However, for this we may want to create another, related ticket.

A would do the task in the following order:

• create the Definition app Module page (on DOCS55)
• create the Definition app App page (on DOCS55)
• Copy the (JCR based) configuration app (and its module page, if there is one) to DOCS55 (and lock the originals)
• Go to DOCS and check the pages which are linked to the https://documentation.magnolia-cms.com/display/DOCS/Configuration+app ... then let's see how to proceed.
  • We may move / copy all these pages then to DOCS55 and link them accordingly (some may link to Configuration app, others may link to Definition app).

How to test / check the definition app?
The 5.5-SNAPSHOT bundles do contain the Definition app, check https://documentation.magnolia-cms.com/display/DOCS55/Release+notes+for+Magnolia+Core+5.5 and download one of the SNAPSHOT bundles there