@RequiresEdt
  private void runBeforeExternalOperation() {
    myMergeContext.putUserData(EXTERNAL_OPERATION_IN_PROGRESS, true);
    enableResolveActions(false);
    getEditor().setViewer(true);

    for (TextMergeChange change : getAllChanges()) {
      change.reinstallHighlighters();
    }
  }
@RequiresEdt
  private void runBeforeExternalOperation()