TYPO3 Core

You're right. This is a missing feature to get IRRE working with flexforms.

Thank you for your quick response.

I wanted to use the simplest comma separated list version that the child need not know its parent, namely a pure alternative to the traditional select type.

It seemed not so difficult to enable this version, so I worked on it for a while with no success.

I don't know whether developer which is responsible for it, the one of flex or you, hopefully it won't be so long that IRRE via flexforms. Because nowadays so many extension developers use flexforms for the configuration of their extensions.

thnaks.