taking verbose = false serious

[SimonDanisch]

Julia 1.0
HTTP.jl v0.6.14

I need to run an HTTP server in an environment where I should not print!
I have some code like this:

handler = HTTP.HandlerFunction(handler_func)
server = HTTP.Server(handler)
server_task = @async (ret = HTTP.serve(server, verbose = false))
tcpref = Ref{Sockets.TCPServer}()
# Start HTTP listen server on port $port_HTTP"
ws_task = @async HTTP.listen(
        baseurl, ws_port, tcpref = tcpref, verbose = false
    ) do s
    is_upgrade(s.message) && upgrade(websocket_handler, s)
end

verbose = false gets me a bit further, but still prints plenty.
I thought maybe I can just set logger = devnull, but that gets me some pretty flaky behavior.
Not sure what exactly happens, but seems like sometimes the server doesn't really start (kind of hard to tell, since now it isn't printing anything anymore :P)

So I guess my question is, why isn't verbose = false just turning off all output - and should it?