I just finished updating my site, only local, from CI3 to CI4. I admit that I didn't believe that I would be able to do it.
Due to my low level of knowledge, I am self-taught, I do not allow myself to criticize, inevitably I would say some nonsense, but some things, by logic, could be better.
I believe that maintaining the legacy, as long as it does not compromise security or does not go head-on against the project's objectives could be maintained. A cuddle for the loyal users.
The manual, despite believing in the efforts of those responsible for it, can still be improved.
Congratulations to the team and, of course, to us as well, users.
So far it has been a great privilege, thank you very much!