Symfony 5.4.0-BETA3 has just been released. Here is a list of the most
important changes:

feature #44125 Add a setter on DateTimeNormalizer to change the default context at runtime (@Seldaek)
bug #44110 [FrameworkBundle] Fix default PHP attributes support in validation and serializer configuration when doctrine/annotations is not installed with PHP 8 (@fancyweb)
bug #44115 [WebProfilerBundle] Tweak the colors of the security panel (@javiereguiluz)
bug #44121 [Serializer] fix support for lazy properties (@nicolas-grekas)
bug #44108 [FrameworkBundle][Messenger] remove FlattenExceptionNormalizer definition if serializer not available (@kbond)
bug #44111 [Serializer] fix support for unset properties on PHP < 7.4 (@nicolas-grekas)
bug #44098 [DependencyInjection] fix preloading (@nicolas-grekas)
bug #44065 [FrameworkBundle] Add framework config for DBAL cache adapter (@GromNaN)
bug #44096 Make ExpressionVoter Cacheable (@jderusse)
bug #44070 [Process] intersect with getenv() to populate default envs (@nicolas-grekas)
feature #43181 Allow AbstractDoctrineExtension implementations to support the newer bundle structure (@mbabker)
bug #44060 [Cache] Fix calculate ttl in couchbase sdk 3.0 (@ajcerezo)
bug #43990 [Translation] [Loco] Generate id parameter instead of letting Loco do it (@welcoMattic)
bug #44043 [Cache] fix dbindex Redis (@a1812)
feature #44015 [Cache] Decrease the probability of invalidation loss on tag eviction (@nicolas-grekas)
bug #44064 [Cache] fix releasing not acquired locks (@nicolas-grekas)
bug #44063 [DependencyInjection] fix creating 2nd container instances (@nicolas-grekas)
bug #44051 [Notifier] Fix package name (@fabpot)
bug #44050 [Notifier] Fix package names (@fabpot)

Want to upgrade to this new release? Because Symfony protects
backwards-compatibility very closely, this should be quite easy. Use
SymfonyInsight upgrade reports
to detect the code you will need to change in your project and
read our upgrade
documentation to learn more.

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