Symfony 6.4.2 has just been released.
Here is the list of the most important changes since 6.4.1:

bug #53282 [RateLimiter] Fix RateLimit->getRetryAfter() return value when consuming 0 or last tokens (@wouterj, @ERuban)
bug #53054 [Cache] Fix expiration time for CouchbaseCollection (@alexandre-daubois)
bug #53259 [RateLimit] Test and fix peeking behavior on rate limit policies (@wouterj)
bug #52406 [Validator] Fix ConstraintsEmail::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 #53243 [Mailer][Postmark] Add missing changelog for webhook support (@OskarStark)
bug #53232 [Notifier] [Smsc] Require login and password (@OskarStark)
bug #53225 [WebProfilerBundle] Fix the design of the compact toolbar button (@javiereguiluz)
bug #52869 [AssetMapper] Improve link generation script (@smnandre)
bug #53203 [Intl] [Emoji] Fix emoji files (remove wrong characters / add missing data) (@smnandre)
bug #53178 [Translation][Crowdin] Use project language mapping (@andrii-bodnar)
bug #53187 [Messenger] Fix using negative delay (@J-roen)
bug #53133 [Validator] Fix using known option names as field names (@HypeMC)
bug #53172 [SecurityBundle] Prevent to login/logout without a request context (@symfonyaml)
bug #52881 [DoctrineBridge] Global query time always at 0.00 ms on profiler (Maxime THIRY)
bug #53173 [FrameworkBundle] add missing webhook services for Brevo and Mailjet (@xabbuh)
bug #53153 [WebProfilerBundle] Fix JS error when evaluating scripts (@jderusse)
feature #53150 [Contracts] Allow psr/container 1.1 again (@derrabus)
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 #53003 [AssetMapper] Fix URL pattern when importing es-module-shims (@hashbanged)
bug #53079 [DoctrineBridge] Add check for lazy object interface (@maxbaldanza)
bug #53061 [Mailer] [Mailjet] Disable tls for mailjet as it should use STARTTLS (@RFreij)
bug #53115 [Serializer] Fix partial denormalization with missing constructor arguments (@HypeMC)
bug #53128 Change ProxyCacheWarmer::warmUp signature (@llupa)
bug #53120 [Translation] add the Phrase translation provider to the UnsupportedSchemeException (@xabbuh)
bug #53125 [Mailer] add the MailPace transport to the UnsupportedSchemeException (@xabbuh)
bug #53081 [Serializer] Keep stack trace for enum value denormalizer error (@kylekatarnls)
bug #53107 [HttpKernel] Don’t validate partially denormalized object (@HypeMC)
bug #52891 [HttpKernel] Fix request attribute value ignored with pinned resolvers (@HypeMC)
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 #53004 [FrameworkBundle] Add missing webhook parsers (@alexandre-daubois)
bug #53007 [FrameworkBundle] Fix webhook parser service removal and add notifier parser service removal (@alexandre-daubois)
bug #52996 [Validator] add missing translation (@xabbuh)
bug #52979 [WebProfilerBundle] Fix „Copy as cURL“ dark style (@HypeMC)
bug #52978 [Webhook] [Framework] Added missing XML attribute in config XSD (@TimoBakx)
bug #52584 [WebProfilerBundle] Fix intercept external redirects (@HeahDude)
bug #52964 [ExpressionLanguage] Fix null coalescing propagation (@fancyweb)
bug #52963 [FrameworkBundle] Fix profiling commands without router (@HeahDude)
bug #52966 [FrameworkBundle] Fix profiling command in web context (@HeahDude)
bug #52937 [WebProfilerBundle] Fix „Copy as cURL“ (@HypeMC)
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 #52870 [SecurityBundle] Fix redeclaration of InternalSecurity class when opcache preload is active (@kaznovac)
bug #52885 [Serializer] fix nullable int cannot be serialized (@nikophil)
bug #52886 [HttpKernel] Catch TypeError if the wrong type is used in BackedEnumValueResolver (@alexandre-daubois)
bug #52878 [WebProfiler] Fix unclosed JS script cannot be parsed (@smnandre)
bug #52867 [Validator] Only trigger deprecation when Validator annotations are used (@HypeMC)
bug #52864 [HttpClient][Mailer][Process] always pass microseconds to usleep as integers (@xabbuh)

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