Symfony version(s) affected: 5.3

Description

The ConfigBuilderCacheWarmer will generate ConfigBuilders for all your extensions (bundles). Since it is a CacheWarmerInterface it will receive the Kernel::getCacheDir() to write the files to.

However, the ConfigBuilders normally lives in the build_dir (Kernel::getBuildDir()). So if you have separate cache and build dirs you will get two sets of ConfigBuilders.

1. All builders in the cache directory
2. The builders you are using in the build directory

There is no issues with this, it is just a bit... weird.