This is very confusing as seen in #12974 or #12906. My suggestion would be "legacy."
handler.send("UnsupportedFeature", {
                featureId: UNSUPPORTED_FEATURES.errorOperatorList,
              });
              sink.error(reason);
              
              
            }
          );
      });
    });
    handler.on("GetTextContent", function wphExtractText(data, sink) {
      var pageIndex = data.pageIndex;
      sink.onPull = function (desiredSize) {};
      sink.onCancel = function (reason) {};
      pdfManager.getPage(pageIndex).then(function (page) {
        var task = new WorkerTask("GetTextContent: page " + pageIndex);
        startWorkerTask(task);
        
        const start = verbosity >= VerbosityLevel.INFOS ? Date.now() : 0;
        page
          .extractTextContent({
            handler,
            task,
            sink,
            normalizeWhitespace: data.normalizeWhitespace,
            combineTextItems: data.combineTextItems,
          })
          .then(