Symfony 5.4.30 has just been released.
Here is the list of the most important changes since 5.4.29:

bug #52332 [Yaml] Fix deprecated passing null to trim() (@javaDeveloperKid)
bug #52343 [Intl] Update the ICU data to 74.1 (@jderusse)
bug #52347 [Form] Fix merging form data and files (ter) (Jan Pintr)
bug #52308 [SecurityBundle] Fix missing login-link element in xsd schema (@fancyweb)
bug #51992 [Serializer] Fix using DateIntervalNormalizer with union types (@Jeroeny)
bug #52276 DB table locks on messenger_messages with many failures (@bn-jdcook)
bug #52283 [Serializer] Handle default context when denormalizing timestamps in DateTimeNormalizer (@mtarld)
bug #52268 [Mailer][Notifier] Update Sendinblue / Brevo API host (@Stephanie)
bug #52255 [Form] Skip merging params & files if there are no files in the first place (@dmaicher, @priyadi)
bug #52201 [HttpKernel] Resolve EBADP error on flock with LOCK_SH with NFS (@driskell)
bug #52105 [Cache] Remove temporary cache item file on rename() failure (@cedric-anne)
bug #52021 [Form] Fix merging params & files when „multiple“ is enabled (@priyadi)
bug #51819 [HttpFoundation] Do not swallow trailing = in cookie value (@OskarStark)
bug #52095 [Notifier][Sendinblue] Handle error responses without a message key (@stof)
bug #51907 [Serializer] Fix collecting only first missing constructor argument (@HypeMC)
bug #52075 [Messenger] Fix DoctrineOpenTransactionLoggerMiddleware (@ro0NL)
bug #52005 [Translation] Prevent creating empty keys when key ends with a period (@javleds)
bug #52035 [DoctrineBridge] Fix DBAL 4 compatibility (@derrabus)
bug #51947 [Cache][Doctrine][DoctrineBridge][Lock][Messenger] Compatibility with ORM 3 and DBAL 4 (@derrabus)
bug #52009 [FrameworkBundle] Configure logger as error logger if the Monolog Bundle is not registered (@MatTheCat)
bug #51969 [FrameworkBundle] Fix calling Kernel::warmUp() when running cache:warmup (@nicolas-grekas)
bug #51985 [WebProfilerBundle] Fix markup to make link to profiler appear on errored WDT (@MatTheCat)
bug #44766 [RateLimiter] TokenBucket policy fix for adding tokens with a predefined frequency (@relo-san)
bug #51858 [Security] Fix resetting traceable listeners (@chalasr)
bug #47342 Change incorrect message, when the sender in the global envelope or the from header of asEmailMessage() is not defined. (@fredericlesueurs)

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