Found something wrong in the original code:
href="'.htmlspecialchars($this->backPath.'db_new.php?id='.$this->id.'&pagesOnly=1returnUrl='.rawurlencode(t3lib_div::getIndpEnv('REQUEST_URI'))).'">'.
==>
'&pagesOnly=1&returnUrl='
The rest is fine, thanks.
A second patch can follow later.
- Franz