diff --git a/snappymail/v/0.0.0/app/libraries/Sabre/Xml/Deserializer/functions.php b/snappymail/v/0.0.0/app/libraries/Sabre/Xml/Deserializer/functions.php
index 5531f7621..949aa720e 100644
--- a/snappymail/v/0.0.0/app/libraries/Sabre/Xml/Deserializer/functions.php
+++ b/snappymail/v/0.0.0/app/libraries/Sabre/Xml/Deserializer/functions.php
@@ -57,7 +57,7 @@ use Sabre\Xml\Reader;
  *
  * @phpstan-return array<string, mixed>
  */
-function keyValue(Reader $reader, string $namespace = null): array
+function keyValue(Reader $reader, ?string $namespace = null): array
 {
     // If there's no children, we don't do anything.
     if ($reader->isEmptyElement) {
@@ -148,7 +148,7 @@ function keyValue(Reader $reader, string $namespace = null): array
  *
  * @phpstan-return list<string>
  */
-function enum(Reader $reader, string $namespace = null): array
+function enum(Reader $reader, ?string $namespace = null): array
 {
     // If there's no children, we don't do anything.
     if ($reader->isEmptyElement) {
@@ -223,6 +223,9 @@ function valueObject(Reader $reader, string $className, string $namespace): obje
                 // Ignore property
                 $reader->next();
             }
+        } elseif (Reader::ELEMENT === $reader->nodeType) {
+            // Skipping element from different namespace
+            $reader->next();
         } else {
             if (Reader::END_ELEMENT !== $reader->nodeType && !$reader->read()) {
                 break;
diff --git a/snappymail/v/0.0.0/app/libraries/Sabre/Xml/LibXMLException.php b/snappymail/v/0.0.0/app/libraries/Sabre/Xml/LibXMLException.php
index 9b5332b3b..5c642a3bf 100644
--- a/snappymail/v/0.0.0/app/libraries/Sabre/Xml/LibXMLException.php
+++ b/snappymail/v/0.0.0/app/libraries/Sabre/Xml/LibXMLException.php
@@ -31,7 +31,7 @@ class LibXMLException extends ParseException
      *
      * @param \LibXMLError[] $errors
      */
-    public function __construct(array $errors, int $code = 0, \Throwable $previousException = null)
+    public function __construct(array $errors, int $code = 0, ?\Throwable $previousException = null)
     {
         $this->errors = $errors;
         parent::__construct($errors[0]->message.' on line '.$errors[0]->line.', column '.$errors[0]->column, $code, $previousException);
diff --git a/snappymail/v/0.0.0/app/libraries/Sabre/Xml/Reader.php b/snappymail/v/0.0.0/app/libraries/Sabre/Xml/Reader.php
index 53d64d54d..a85bd058c 100644
--- a/snappymail/v/0.0.0/app/libraries/Sabre/Xml/Reader.php
+++ b/snappymail/v/0.0.0/app/libraries/Sabre/Xml/Reader.php
@@ -107,7 +107,7 @@ class Reader extends \XMLReader
      *
      * @return array<int,array<string, mixed>>
      */
-    public function parseGetElements(array $elementMap = null): array
+    public function parseGetElements(?array $elementMap = null): array
     {
         $result = $this->parseInnerTree($elementMap);
         if (!is_array($result)) {
@@ -132,7 +132,7 @@ class Reader extends \XMLReader
      *
      * @return array<int,array<string, mixed>>|string|null
      */
-    public function parseInnerTree(array $elementMap = null)
+    public function parseInnerTree(?array $elementMap = null)
     {
         $text = null;
         $elements = [];
diff --git a/snappymail/v/0.0.0/app/libraries/Sabre/Xml/Service.php b/snappymail/v/0.0.0/app/libraries/Sabre/Xml/Service.php
index cb9a5175b..ad18b6f4e 100644
--- a/snappymail/v/0.0.0/app/libraries/Sabre/Xml/Service.php
+++ b/snappymail/v/0.0.0/app/libraries/Sabre/Xml/Service.php
@@ -107,7 +107,7 @@ class Service
      *
      * @throws ParseException
      */
-    public function parse($input, string $contextUri = null, string &$rootElementName = null)
+    public function parse($input, ?string $contextUri = null, ?string &$rootElementName = null)
     {
         if (is_resource($input)) {
             // Unfortunately the XMLReader doesn't support streams. When it
@@ -151,7 +151,7 @@ class Service
      *
      * @throws ParseException
      */
-    public function expect($rootElementName, $input, string $contextUri = null)
+    public function expect($rootElementName, $input, ?string $contextUri = null)
     {
         if (is_resource($input)) {
             // Unfortunately the XMLReader doesn't support streams. When it
@@ -200,7 +200,7 @@ class Service
      *
      * @param string|array<int|string, mixed>|object|XmlSerializable $value
      */
-    public function write(string $rootElementName, $value, string $contextUri = null): string
+    public function write(string $rootElementName, $value, ?string $contextUri = null): string
     {
         $w = $this->getWriter();
         $w->openMemory();
@@ -241,7 +241,6 @@ class Service
     public function mapValueObject(string $elementName, string $className): void
     {
         list($namespace) = self::parseClarkNotation($elementName);
-        $namespace = $namespace ?? '';
 
         require_once __DIR__ . '/Deserializer/functions.php';
         $this->elementMap[$elementName] = function (Reader $reader) use ($className, $namespace) {
@@ -265,7 +264,7 @@ class Service
      *
      * @throws \InvalidArgumentException
      */
-    public function writeValueObject(object $object, string $contextUri = null): string
+    public function writeValueObject(object $object, ?string $contextUri = null): string
     {
         if (!isset($this->valueObjectMap[get_class($object)])) {
             throw new \InvalidArgumentException('"'.get_class($object).'" is not a registered value object class. Register your class with mapValueObject.');
@@ -284,7 +283,7 @@ class Service
      *
      * If the string was invalid, it will throw an InvalidArgumentException.
      *
-     * @return array{string|null, string}
+     * @return array{string, string}
      *
      * @throws \InvalidArgumentException
      */
diff --git a/snappymail/v/0.0.0/app/libraries/Sabre/Xml/Version.php b/snappymail/v/0.0.0/app/libraries/Sabre/Xml/Version.php
index 1b3b4f9b3..f38e87c27 100644
--- a/snappymail/v/0.0.0/app/libraries/Sabre/Xml/Version.php
+++ b/snappymail/v/0.0.0/app/libraries/Sabre/Xml/Version.php
@@ -16,5 +16,5 @@ class Version
     /**
      * Full version number.
      */
-    public const VERSION = '4.0.4';
+    public const VERSION = '4.0.5';
 }
diff --git a/snappymail/v/0.0.0/app/libraries/Sabre/Xml/Writer.php b/snappymail/v/0.0.0/app/libraries/Sabre/Xml/Writer.php
index e7d7eb941..77bdae02c 100644
--- a/snappymail/v/0.0.0/app/libraries/Sabre/Xml/Writer.php
+++ b/snappymail/v/0.0.0/app/libraries/Sabre/Xml/Writer.php
@@ -125,7 +125,6 @@ class Writer extends \XMLWriter
         if ('{' === $name[0]) {
             list($namespace, $localName) =
                 Service::parseClarkNotation($name);
-            $namespace = $namespace ?? '';
 
             if (array_key_exists($namespace, $this->namespaceMap)) {
                 $result = $this->startElementNS(
@@ -240,7 +239,6 @@ class Writer extends \XMLWriter
             $localName
         ) = Service::parseClarkNotation($name);
 
-        $namespace = $namespace ?? '';
         if (array_key_exists($namespace, $this->namespaceMap)) {
             // It's an attribute with a namespace we know
             return $this->writeAttribute(