I don't believe we have anything to pass here for cancellation.

that's fine. we'll continue to have the parameter though in case this is something you hookup in the future. for example, i could imagine a world where the user decides to close VS while we're still loading everything. This would allow youto thread though cancellation if you wanted us to abort.

Our positionhere is: we will support cancellation up through the point where we're still doing computation but haven't done any mutation. once we mutate our actual internal state, we ignore caller-requested cancellation and finish what we're doing. That way our internal models are always in a consistent state.

We don't expliictly reference the StreamJsonRpc package anywhere in this solution, so this line had no effect.

A package upgrade must have introduced a Debugger class into a Microsoft.* namespace, as this broke. A using alias didn't help either, hence the fully qualified name here.

If you put using System.Diagnostics; inside the namespace (not above it like it is now), it would have used the right debugger class as an alternative to fully qualifying it.