In order to reduce complexity on xwiki.org instance and make it easier to manage the playground wiki (which used to be located on https://playground.xwiki.org) we decided to move it to its own dedicated instance on https://www.xwikiplayground.org.
The main difference for now is you cannot use your xwiki.org account to edit on it, you need to register an account (which is going to be wiped every day like the rest of the wiki).
We might also decide to open up new feature on playground that used to be impossible for security reason when it was a subwiki of the xwiki.org instance. Still need to be discussed.
