[1] 
The [DFN@en[[CODE(CSS)@en[:[[-manakai-contains]]([VAR@en[s]])]]]]
pseudo-class has the same semantics and syntax as of
[CODE(CSS)@en[:[[contains]]([VAR@en[s]])]] pseudo-class
<http://www.w3.org/TR/2001/CR-css3-selectors-20011113/#content-selectors>.

[2]
The [DFN@en[[CODE(CSS)@en[:[[-manakai-current]]]]]]
pseudo-class represents an element that is currently
selected for the purpose of querying (known as
[DFN@en[current element]]).

Unless explicitly defined by a specification, current element is 
null and therefore no element matches with this pseudo-class.

For selectors specified in the first argument of
[CODE(DOMm)@en[[[querySelector]]]] or
[CODE(DOMm)@en[[[querySelectorAll]]]] method
of [CODE(DOMi)@en[[[ElementSelector]]]] interface,
the current element is the element on which
the method is invoked.

;; 
For example, a Perl subroutine:
[PRE(perl example code)[
sub {
  $doc->inner_html
      (q[<section><p></p><p></p><section><p></p></section><p></p></section>]);
  my $section = $doc->get_elements_by_tag_name ('section')->[0];
  return @{$section->query_selector (':-manakai-current > p')};
};
]PRE]
... will return an array of three [CODE(DOMi)@en[[[Element]]]]
nodes: first, second, and fourth [CODE(HTMLe)@en[[[p]]]]
elements, but third [CODE(HTMLe)@en[[[p]]]] element
in the child [CODE(HTMLe)@en[[[section]]]] element will not
returned.  Note that 
[CODE(perl code example)@en[$doc->query_selector (':-manakai-current > p')]]
will return no node, since current element is not defined
for the [CODE(DOMi)@en[[[DocumentSelector]]]] interface.