minor #9630 [Serializer] example for processing XML comments when decoding (snoek09, javiereguiluz)

This PR was merged into the master branch.

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[Serializer] example for processing XML comments when decoding

This fixes #9483.

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dc01b87 Reword
8d99047 example for processing XML comments when decoding

Author: javiereguiluz

components/serializer.rst

@@ -704,6 +704,15 @@ always as a collection.
 .. versionadded:: 4.1
     The ``as_collection`` option was introduced in Symfony 4.1.
 
+.. tip::
+
+    XML comments are ignored by default when decoding contents, but this
+    behavior can be changed with the optional ``$ignoredNodeTypes`` argument of
+    the ``XmlEncoder`` class constructor.
+
+    .. versionadded:: 4.1
+        XML comments are ignored by default starting from Symfony 4.1.
+
 The ``YamlEncoder``
 ~~~~~~~~~~~~~~~~~~~