Symfony 6.3.6 has just been released.
Here is the list of the most important changes since 6.3.5:

• bug #52201 [HttpKernel] Resolve EBADP error on flock with LOCK_SH with NFS (@driskell)
• bug #52194 [Validator] Handle null case (@OskarStark)
• bug #52158 [Messenger] Fix graceful exit with ids (@HypeMC)
• 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 #52080 [Messenger] Fix graceful exit (@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 #52040 [Cache] Fix ArrayAdapter::freeze() return type (@fancyweb)
• bug #52036 [Cache][VarExporter] Fix proxy generation to deal with edgy behaviors of internal classes (@nicolas-grekas)
• bug #51947 [Cache][Doctrine][DoctrineBridge][Lock][Messenger] Compatibility with ORM 3 and DBAL 4 (@derrabus)
• bug #51972 [HttpKernel] Handle nullable callback of StreamedResponse (@elementaire)
• bug #52017 [Mailer] Capitalize sender header for Mailgun (@Romanavr)
• 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 #51825 Fix order array sum normalizedData and nestedData (@jerowork)
• bug #51876 [HttpClient] Fix type error with http_version 1.1 (@Filnor)
• bug #51858 [Security] Fix resetting traceable listeners (@chalasr)
• bug #51843 [FrameworkBundle] Fix call to invalid method in NotificationAssertionsTrait (@ker0x)
• bug #51791 [Messenger] Check if PCNTL is installed (@HypeMC)
• 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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