Group mail broken when embedding OO in frame

How to reproduce

• Create a group
• Enable mail form
• Create plain vanilla HTML page with frameset, embedd OOin frameset (see attached html page)
• Open OO in frameset, go to group
• In Group, open Mail form
  -> NOK: mail form is empty, should contain link to group
• add some text, send mail
  -> NOK: mail sent to local mailbox contains the text that should have appeared in the form in the first place, entered input id discarded

If this is only the problem in that form, well not to dramatic. But I assume this has something to do with the 10.4 iframe-to-ajax refactoring, thus it might affect other places as well. We need to investigate to see what is causing this problem (some parent window search that goes to far).

Testsetup available on test8, login as "administrator".

Reported by Saty from HFU