https://github.com/Tuurlijk/typo3scan
I use an old ubuntu-laptop running this as standalone application.
„This tool scans a folder for any code that is broken or deprecated. It’s a wrapper around the TYPO3 scanner library that has been extracted from the TYPO3 v9 core. You can scan for deprecations and breaking changes for v7, v8, v9 and v10.“
Fantastic tool from Michiel Roos, wrapping Oliver Hader’s library.