I got one project which uses helhum/typo3-config-handling.
I therefore needed to adjust the config to return the final result, as
the package expects an array instead of globals.
It also loads config multiple times. I therefore needed to remove
require_once and replace by require. But some code can't be required
multiple times and was moved to dedicated files with require_once.
This package prevents writing back silent upgrades, I therefore needed
to clean up the very old configs for TYPO3 < 10.