This is based upon Polymer 2 (Web Components) and is implemented as a standalone application.
Please note, that this is still a beta version and some things may still be quirky. Please report to the Github issues if you find something.
Main goal was to make user management independent of betterFORM (Dojo) and improve the UI of the older version.
If you just want a quick look - it's also available from public repo and can be installed via Package Manager. But please note that this version is an optimized one and shouldn't be used for code-digging or patching.