by adding a group to a moodleform with $mform->addGroup
if the group is not contained in a fieldset, its position in the form is strongly on the right in formal_white.

I am sorry, but I noticed this issue by coding!
I did not find any other instance in moodle core of this situation so... the only way to test this bug is to add to a moodleform BEFORE an 'header 'a code like:

$option = array('a label');

$elementgroup = array();

$elementgroup[] =& $mform->createElement('select', 'aaa', '', $option);

$elementgroup[] =& $mform->createElement('text', 'bbb', '');

$mform->addGroup($elementgroup, 'group', 'one more label', ' ', false);

and call the modified form from moodle.