Composer require/remove vendor code does not update autoloader (APCu cached)

Potential solution here: 📌 Use a better container cache key Active

I'll close this in preference to above.

Thanks for your thorough Issue Summary @ekes, and for guiding me to the 📌 Use a better container cache key Active issue, I would never have found it without your help :)

In fact, I think it could be worth considering to add parts of this Issue Summary to the container cache key issue being worked on, to add some context. Or we can hope that people searching for a solution to the APCu cache challenge finds this issue, and get guided to it?