FoldRegion getFoldingPlaceholderAt(@NotNull EditorLocation location, boolean ignoreCustomRegionWidth) {
    Point p = location.getPoint();
    if (p.y < location.getVisualLineStartY() || p.y >= location.getVisualLineEndY()) {
      // block inlay area
      return null;
    }
    FoldRegion region = location.getCollapsedRegion();
    return !ignoreCustomRegionWidth && region instanceof CustomFoldRegion &&
           p.x >= myEditor.getContentComponent().getInsets().left + ((CustomFoldRegion)region).getWidthInPixels() ? null : region;
  }
FoldRegion getFoldingPlaceholderAt(@NotNull EditorLocation location, boolean ignoreCustomRegionWidth)