Ziao has published a new git repo: "Phaser 3 has officially been released, but due to time constrains, some features have been left for now. One of the most important features that I am missing is Containers. They are similar to groups, but they allow you to manipulate them as if they were a sprite. For example, you can set their alpha, rotation, position, etc. Groups are mainly aimed at organizing your sprites, and do not have these features.
This repository will be marked as deprecated as soon as Phaser launches their version of Containers, which will no doubt be superior. Code was written in old-school javascript as much as possible, to avoid the need for transpiling."