@ApiStatus.Internal
  public @NotNull RangeMarker createFocusRegion(int start, int end) {
    RangeMarkerEx marker = new RangeMarkerImpl(myEditor.getDocument(), start, end, false, false);
    myFocusMarkerTree.addInterval(marker, start, end, false, false, true, 0);
    mySegmentListeners.forEach(l -> l.focusRegionAdded(marker));
    return marker;
  }
@ApiStatus.Internal
  public @NotNull RangeMarker createFocusRegion(int start, int end)