You’re probably referring to this: Have you tried using Spectrum Web Components yet to build your plugin UI? - #32 by tomzag
While this approach works fine for tooltips, it doesn’t work well for context menus. It behaves more like a modal dialog, where only one window can be open at a time. Nested submenus require multiple layers/windows, which makes it impossible to achieve with this method. And even if it were possible, the implementation would be overly complex and impractical.