Description
In result code of every portal pages there are much strings:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
This is because layout.vm contains this word at the start of file. So, I think, this string has to be clear out from layout.vm to another place, to achieve only one DOCTYPE string per portal page