List<RangeHighlighter> (@NotNull Editor editor, int offset1, int offset2, @NotNull SeparatorPresentation presentation) { RangeHighlighter marker = editor.getMarkupModel() .addRangeHighlighter(null, offset1, offset2, LINE_MARKER_LAYER, HighlighterTargetArea.LINES_IN_RANGE); DiffLineSeparatorRenderer renderer = new DiffLineSeparatorRenderer(editor, presentation); marker.setLineSeparatorPlacement(SeparatorPlacement.TOP); marker.setLineSeparatorRenderer(renderer); marker.setLineMarkerRenderer(renderer); return Collections.singletonList(marker); }