Symfony 5.4.34 has just been released.
Here is the list of the most important changes since 5.4.33:

• bug #52406 [Validator] Fix Constraints\Email::ERROR_NAMES (@mathroc)
• bug #53140 [Serializer] Skip uninitialized properties with deep_object_to_populate (@mtarld)
• bug #53195 [HttpKernel] Fix default locale is ignored when set_locale_from_accept_language is used (@jkobus)
• bug #52928 [Dotenv] Allow environment variables starting with an underscore (@xabbuh)
• bug #53232 [Notifier] [Smsc] Require login and password (@OskarStark)
• bug #53187 [Messenger] Fix using negative delay (@J-roen)
• bug #53133 [Validator] Fix using known option names as field names (@HypeMC)
• bug #53153 [WebProfilerBundle] Fix JS error when evaluating scripts (@jderusse)
• bug #52998 [Notifier] [Bridges] Provide EventDispatcher and HttpClient to the transport (@rdavaillaud)
• bug #52817 [Serializer] Do not instantiate object if it is not instantiable (@maxbaldanza)
• bug #53079 [DoctrineBridge] Add check for lazy object interface (@maxbaldanza)
• bug #53115 [Serializer] Fix partial denormalization with missing constructor arguments (@HypeMC)
• bug #53081 [Serializer] Keep stack trace for enum value denormalizer error (@kylekatarnls)
• bug #53057 [HttpKernel] Move @internal from AbstractSessionListener class to its methods and properties (@Florian-Merle)
• bug #52990 [TwigBridge] don't use deprecated and internal Twig functions (@xabbuh)
• bug #52996 [Validator] add missing translation (@xabbuh)
• bug #52940 [Console] Fix color support check on non-Windows platforms (@theofidry)
• bug #52896 [Messenger] Avoid reconnecting active Redis connections. (@BusterNeece)
• bug #52923 Avoid incompatibility with symfony/console 7 (@jdecool)
• bug #52927 [Dotenv] Properly handle SYMFONY_DOTENV_VARS being the empty string (@xabbuh)
• bug #52935 [Validator] Missing translations for Slovak (sk) #51954 (Jan Vernarsky)
• bug #52941 [Console] Fix xterm detection (@theofidry)
• bug #52795 [FrameworkBundle] do not overwrite an application's default serialization context (@xabbuh)
• bug #52885 [Serializer] fix nullable int cannot be serialized (@nikophil)
• bug #52864 [HttpClient][Mailer][Process] always pass microseconds to usleep as integers (@xabbuh)

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