Expand on SingleResult may cause request to never finish

After upgrading from v7 to v8 I'm running into some issues. One is that some requests simply never return a response. I cannot figure out what is causing this.

I have a basic controller which looks like this:

[EnableQuery]
public IQueryable<SalesOrderLine> Get()
{
    return Context.SalesOrderLines;
}

[EnableQuery(MaxExpansionDepth = 3)]
public SingleResult Get(int key)
{
    return SingleResult.Create(Context.SalesOrderLines.Where(l => l.SalesOrderLineId == key));
}

The weird thing is when I call the second endpoint without $expand, it returns a response. However, when I include $expand for any expandable property on my SalesOrderLine, the request doesn't finish until it times out. In the logs I only see this:

Microsoft.AspNetCore.Mvc.Infrastructure.ObjectResultExecutor[1]
      Executing ObjectResult, writing value of type 'Microsoft.AspNetCore.OData.Query.Wrapper.SelectAllAndExpand`1[[MyNamespace.SalesOrderLine, MyNamespace, Version=2.23.0.0, Culture=neutral, PublicKeyToken=null]]'.

Strangely, when I call the first endpoint (returning a collection instead of a single result) it works fine, including $expand. Also, I only have this problem on certain controllers, on others $expand works fine on SingleResult. Any thoughts?

Start with the two controller entry points shown: the collection action and the SingleResult action, and reproduce the timeout using $expand on an expandable SalesOrderLine property. Compare their request and response behavior with the logged ObjectResult type; done means the SingleResult endpoint completes successfully with $expand instead of timing out.