line numbers arent visible in CodeArea

public void createNewTab() {
        Tab tab = new Tab("Untitled");

        // Create a CodeArea (RichTextFX)
        CodeArea codeArea = new CodeArea();

        // Set the line numbers on the left of the CodeArea
        codeArea.setParagraphGraphicFactory(LineNumberFactory.get(codeArea));
        
        // Set the content of the tab
        tab.setContent(codeArea);

        // Add the tab to the TabPane
        tabPane.getTabs().add(tab);

        // Select the newly created tab
        tabPane.getSelectionModel().select(tab);
    }

public void createNewTab() {
        Tab tab = new Tab("Untitled");

        // Create a CodeArea (RichTextFX)
        CodeArea codeArea = new CodeArea();

        // Set the line numbers on the left of the CodeArea
        codeArea.setParagraphGraphicFactory(LineNumberFactory.get(codeArea));
        
        // Set the content of the tab
        tab.setContent(codeArea);

        // Add the tab to the TabPane
        tabPane.getTabs().add(tab);

        // Select the newly created tab
        tabPane.getSelectionModel().select(tab);
    }