Adjacent text nodes after update

Adjacent text nodes can be obtained after an XQU update.

In the following query the adjacent text nodes "a-b" and "b-c" should be merged but they are not.

variable $doc:=<root>root-a<a/>a-b<b/>b-c<c/>c-d<d/>d-root</root>;
variable $a:=();
variable $b:=();

$a:=count($doc/text());
replace node $doc/b with ();

$b:=count($doc/text());

trace($doc,"dump");

<result>rep-empty: before: {$a}, after: {$b}, expected {$a - 1}</result>

Result:

<?xml version="1.0" encoding="UTF-8"?>
dump [0]: <root-elem nid="50| 1.1"><text nid="5a| 1.1.3">root-a</text><a-elem nid="5c|80| 1.1.5"></a-elem>

<text nid="5d|80| 1.1.7">a-b</text><text nid="5e|30| 1.1.11">b-c</text>

<c-elem nid="5e|50| 1.1.13"></c-elem><text nid="5e|70| 1.1.15">c-d</text><d-elem nid="5e|90| 1.1.17"></d-elem><text nid="5e|b0| 1.1.19">d-root</text></root-elem>
<result>rep-empty: before: 5, after: 5, expected 4</result>