v0.21.2

exactly the same as 0.21.1 ;-)

NOTE : Seems stable in gunicorn or uvicorn.
(in fact, I thought it was not stable, because I used to test into the same navigator (chrome + private chrome), and it seems that they share some tcp sockets, and generates some troubles in server side ... and so : it was not a good idea ! With 2 different navigator : no trouble at all)