• Drawers are not mobile-only. Most desktop apps will probably opt for sidebars instead of drawers on desktop, but if you want to allow users to show some UI elements only on demand, a drawer can make sense even on desktop. They just work slightly differently (on desktop the drawer stays open until you close it manually), but that should be described within the page. It's still the same pattern
• As far as I know, Kirigami does not have a menubar and so far doesn't plan to have one, so that would be QWidget-only
• Plasma does have context menus
• Currently Kirigami uses toolbars only on desktop (on mobile they are floating action buttons). This might change in the future, but for the time being, toolbars are desktop-only

I'll go ahead and edit the description accordingly

Column-based navigation can also work just fine on the desktop in QWidgets-based apps, too. No reason to shut the door to that option IMHO.

Thanks!