Custom hostname not working

[Nikishek]

Whatever hostname I set, I still get a hostname in the format "esp32-[MAC]".
A quick solution or rather workaround is to put WiFi.setHostname(mdnsName); at the beginning of the WifiSetup() or setup().
How should it be done properly?

There is also another unrelated problem that the custom URL_HOSTNAME doesn't work. I guess it's probably more of a problem on my router.