@Override
  public VcsDependentHistoryComponents getUICustomization(final VcsHistorySession session, JComponent forShortcutRegistration) {
    final ColumnInfo<?, ?>[] columns;
    final Consumer<VcsFileRevision> listener;
    final JComponent addComp;
    if (((SvnHistorySession)session).isHaveMergeSources()) {
      final MergeSourceColumnInfo mergeSourceColumn = new MergeSourceColumnInfo((SvnHistorySession)session);
      columns = new ColumnInfo[]{new CopyFromColumnInfo(), mergeSourceColumn};

      final JTextArea field = new JTextArea() {
        final StatusText statusText = new StatusText(this) {
          @Override
          protected boolean isStatusVisible() {
            return getDocument().getLength() == 0;
          }
        };

        @Override
        public Color getBackground() {
          return UIUtil.getEditorPaneBackground();
        }

        {
          statusText.setText(message("status.text.merge.sources"));
          setEditable(false);
          setWrapStyleWord(true);
          setLineWrap(true);
        }

        @Override
        protected void paintComponent(Graphics g) {
          super.paintComponent(g);
          statusText.paint(this, g);
        }
      };
      listener = vcsFileRevision -> {
        field.setText(mergeSourceColumn.getText(vcsFileRevision));
        field.setCaretPosition(0);
        field.repaint();
      };

      final MergeSourceDetailsAction sourceAction = new MergeSourceDetailsAction();
      sourceAction.registerSelf(forShortcutRegistration);

      JPanel fieldPanel = new ToolbarDecorator() {
        @Override
        protected @NotNull JComponent getComponent() {
          return createScrollPane(field, true);
        }

        @Override
        protected void updateButtons() {
        }

        @Override
        protected void installDnDSupport() {
        }

        @Override
        protected boolean isModelEditable() {
          return false;
        }
      }.initPosition()
        .addExtraAction(sourceAction)
        .createPanel();
      fieldPanel.setBorder(JBUI.Borders.empty());
      addComp = fieldPanel;
    }
    else {
      columns = new ColumnInfo[]{new CopyFromColumnInfo()};
      addComp = null;
      listener = null;
    }
    return new VcsDependentHistoryComponents(columns, listener, addComp);
  }
@Override
  public VcsDependentHistoryComponents getUICustomization(final VcsHistorySession session, JComponent forShortcutRegistration)