anchor.diff:                  let! symbolReferences = MDLanguageService.Instance.GetUsesOfSymbolAtLocationInFile (projectFilename, currentFile, source, files, line, col, lineStr, args)
                   return symbolReferences
               with
  -            | :? OperationCanceledException -> return None
  +            | :? Threading.Tasks.TaskCanceledException -> return None
               | exn -> LoggingService.LogError("Unhandled Exception in F# HighlightingUsagesExtension", exn)
                        return None })
               
  
positive.code:                 | _ -> Seq.empty
                                  
              with
              | :? OperationCanceledException -> Seq.empty
              | exn -> LoggingService.LogError("Unhandled Exception in F# HighlightingUsagesExtension", exn)
                       Seq.empty  
  
negative.code: 
      override x.Initialize() =
          base.Initialize ()
          let syntaxMode = new FSharpSyntaxMode (x.Editor, x.DocumentContext)
          x.Editor.SemanticHighlighting <- syntaxMode
  
      override x.ResolveAsync (token) =
          Async.StartAsTask (
  