Open attachment 189413 [details], and use this code:

sub TestContentControlImportedObjects
  paragraphs = thisComponent.getText().createEnumeration()
  para1 = paragraphs.nextElement()
  runs1 = para1.createEnumeration()
  run1 = runs1.nextElement()
  para2 = paragraphs.nextElement()
  runs2 = para2.createEnumeration()
  run2 = runs2.nextElement()

  MsgBox run1.getString()
  MsgBox run2.getString()
  MsgBox run2.ContentControl.getString()
end sub

The document has two paragraphs, each having a content control with a placeholder text. Because the first one is a block control (which content includes the respective paragraph), and the second is an inline control (contained in the paragraph, and the content includes only a run), these two are imported differently (as of 2023-09-07): the first one as a field, and the second one as a content control.

The three MsgBox calls in the end of the code are expected to show the same "Click or tap here to enter text." string. However, the second call showing "run2.getString()" produces an empty message.

This happens because lcl_CreateContentControlPortion in sw/source/core/unocore/unoportenum.cxx is called with pUnoCursor pointing to the end of the paragraph. Looks like it needs to take into account the values of rAttr (and respective SwContentControl), and pPortions, which may contain the range that should become the actual cursor.