If you run the Editor as a game (i.e. when doing Standalone PIE) you’ll also have to set it. The check is in FUdpMessagingModule::SupportsNetworkedTransport(). There has been a regression recently, and depending on which version you’re using, the logic may differ. The latest version is:
bool SupportsNetworkedTransport() const
{
// disallow unsupported platforms
if (!FPlatformMisc::SupportsMessaging())
{
return false;
}
// single thread support not implemented yet
if (!FPlatformProcess::SupportsMultithreading())
{
return false;
}
// always allow in standalone Slate applications
if (!FApp::IsGame() && !IsRunningCommandlet())
{
return true;
}
// otherwise only allow if explicitly desired
return FParse::Param(FCommandLine::Get(), TEXT("Messaging"));
}
Like I said, I hope to get rid of this at some point, but for now we don’t want the UDP transport to be turned on everywhere, because it still has some issues.