The query is K2-ExternalVariablesWithout-10 is:

declare variable $e := <e>
    <a/>
</e>;
declare variable $f := $e;
<r>
{
    $e is $e,
    $f is $e,
    $e, $f
}
</r>


The expected result is:

<r>true true<e> <a/></e><e><a/></e></r>

I believe that it has an extra space and that it should be:

<r>true true<e><a/></e><e><a/></e></r>