minor #14650 [Debug] Added option to specify the event dispatcher in debug:event-dispatcher (TimoBakx)

This PR was merged into the 5.3-dev branch.

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[Debug] Added option to specify the event dispatcher in debug:event-dispatcher

Documentation for symfony/symfony#39276

Part of #SymfonyHackday

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9695d7e [Debug] Added option to specify the event dispatcher in debug:event-dispatcher

Author: javiereguiluz

event_dispatcher.rst

@@ -322,6 +322,18 @@ its name:
 
     $ php bin/console debug:event-dispatcher kernel.exception
 
+For the :doc:`new experimental Security </security/experimental_authenticators>`
+an event dispatcher per firewall was added. You can get the registered listeners
+for a particular event dispatcher by using the ``--dispatcher`` option:
+
+.. code-block:: terminal
+
+    $ php bin/console debug:event-dispatcher --dispatcher=security.event_dispatcher.main
+
+.. versionadded:: 5.3
+
+    The ``dispatcher`` option was introduced in Symfony 5.3.
+
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