Additional columns in entities in v6.1+

[jovi]

After updating to 6+ I see some changes in ORM. Looks like just removed "getLinkMultipleCollection" without providing alternatives and this change not documented.

Most of my fields with additionalColumns in EntityDef now working with bugs. Related to UI, field still show inputs for columns, but always empty. If I put something to input and save - it send's to API normally like before, but after refresh API return something like:

{
  id: ....
  name: ....
  usersColumns: {
    5f7311e....270def: {
       projectRole: null <---- always null in all my entities
    }
  }
}

This is a bug or new changes? What I can do to restore my functionality regarding to new API

[item]

Aie... if i understand, it's not 6.1+ but 6.0

it's custom field in middleTable ?
what's additionalColumns ?