Unable to start language server (?)

I'm considering using the OmniSharp LanguageServer for one of my projects, but was unable to get the server to start. I read all of the documentation I could find and followed the implementation of the sample server, but still could not figure out what was wrong. I even tried running the sample server as-is, but could not get that to work.

The application gets as far as line 246 in LanguageServer.cs, where it will await _initializingTask.ConfigureAwait(false);, which never runs to completion.

At this point, the server does not respond to any messages passed on the input stream. Connecting with a client (lsp4intellij) fails, and sending an initialisation message manually by pasting it into stdin yields no response. It does not even give you any errors if you send a malformed message or just plain gibberish.

I'm running this on MacOS 13.0, and tried both .NET 6.0 and 7.0.

Start at line 246 of LanguageServer.cs, where the server awaits _initializingTask, and reproduce the sample server failure using the stdin input path described in the issue. Compare the sample server's initialization flow with the behavior on macOS under .NET 6 or 7. Done means the server completes initialization and responds to a valid initialization message, with malformed input producing observable handling rather than silence.