Wojciech Trocki yes it should be 'playground'. I've seen the tab still being called 'query'. Could we get that updated?
If there is any outstanding tasks we want to do to improve the experience of the playground. i.e. fixing the buggyness can you create JIRAs under the epic for it.
In relation to styling we can do some small updates but remember the approach here is to not sync too much time on this one.