From issue #270:
[quote]On RemoteFunctions, if InvokeClient is called on the server, but OnClientInvoke was not defined on the target client, then the call to InvokeClient will never finish. The expected behavior is that, if InvokeClient is called, but OnClientInvoke is not yet defined, then the RemoteFunction will wait, and call it immediately after it has been defined.
It may be worth noting that the correct behavior occurs in the studio’s Play Solo mode, which acts as both the server and a client.
It is also worth noting that the correct behavior occurs with InvokeServer and OnServerInvoke.
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It would neat if this could get fixed nice and quick. It is possible to work around it, but that’s extra complexity that isn’t fun to deal with.