Error 500: "Chunked encoding is not supported and the content-length header is required." when joining a room

[Snirozu]

as the title says, this problem both happens on 0.15.3 and 0.15.4 but not on 0.15.2, also I've checked all of my libraries and all are up to date

found the same issue on https://github.com/orgs/colyseus/discussions/735 and https://github.com/colyseus/colyseus-haxe/issues/61 and no one seemed to fix it