Preparing Your Apps and Bundles for Symfony 6

According to Symfony Release Process, every two years Symfony releases the last version of a branch (X.4) and the first version of the next branch (Y.0) at the same time. That will happen at the end of November 2021, when both Symfony 5.4 and Symfony 6.0 will be released. The main difference between them is that Symfony 5.4 will still contain all deprecated features and you can use it in applica
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