Steps to reproduce

1.  Create a composite dialog which contains some i18n fields, e.g:

   form:
     tabs:
       - name: tabEvent
         label: Event
         fields:
           - name: event1
             fieldType: composite
             fields:
               - name: title
                 fieldType: text
                 i18n: true
               - name: date
                 fieldType: date
                 label: tabEvent.event1.date.label
           - name: event2
             fieldType: composite
             fields:
               - name: title
                 fieldType: text
                 i18n: true
               - name: date
                 fieldType: date
                 label: tabEvent.event2.date.label
   actions:
     commit:
       class: info.magnolia.ui.admincentral.dialog.action.SaveDialogActionDefinition
     cancel:
       class: info.magnolia.ui.admincentral.dialog.action.CancelDialogActionDefinition 

1.  Create the component and once it is open, change the language
2. Check the label of the composite field is lost and doesn't come back even switching back to the original language

Expected results

The composite field label is not deleted

Actual results

The composite field label disappears 

Workaround

N/A 

Development notes

It also happens if declaring component with the new UI