I'm sorry if I'm posting this in the wrong place, or if this isn't the place at all. But I want to propose a suggestion. Feel free to remove this if I'm in the wrong place. :)
My main gripe with the Kirigami framework is that while it provides a typical and appropriate interface on devices with small screens, it never really feels at home on desktop, mostly just feeling like a stretched-out phone app. The main thing I am missing is a classic horizontal menu bar, with clear text to indicate each section and a dropdown with icons and text for each alternative. To me there is no more user-friendly and obvious way to present a large amount of functions. A toolbar with text next to icons works decent for a few options, but not so much when they are many, leading to many functions getting hidden deeper and deeper down between more and more clicks. It's usually neither userfriendly or accessible. Even if the sidebar is displayed at all times, it's less space-efficient and often still requires switching "back and forth" between various views.
So I was thinking, how about if it worked like on most webpages instead, where all options hidden under the hamburger menu on mobile "folds out" into a traditional horizontal menu once there is enough horisontal space? One vertical and one horizontal like a typical webpage navbar: https://www.w3schools.com/css/css_navbar.asp
It works perfect for pretty much all of the internet, and it should be easy to do submenus and such too. (A clear example can be found here: https://www.kadencewp.com or here: https://pressmaximum.com/customify/?builder=elementor&demo=customify-2018)