Symfony 5.3.6 has just been released. Here is a list of the most
important changes:

bug #42307 [Mailer] Fixed decode exception when sendgrid response is 202 (@rubanooo)
bug #42296 [Dotenv][Yaml] Remove PHP 8.0 polyfill (@derrabus)
bug #42274 [VarDumper] HtmlDumper::setDumpHeader() accepts null (@rrpadilla)
bug #42289 [HttpFoundation] Fixed type mismatch (@Toflar)
bug #42259 [Security] fix Check if it has session before getSession() (@mousezheng)

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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version is not maintained anymore? Or only when a security issue is fixed?
Consider subscribing to the Symfony Roadmap Notifications.

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