Make toggle useful or hide without CSS

Where CSS is disabled, the toggle shows and controls Dark/Light mode state but that control is only of what's in Local Storage, there's no visual change to the page.

The toggle could change page appearance, even when CSS is off, by changing the page's <meta name="color-scheme"> content, e.g. from "light dark" to just "dark". Of course, this can only occur on pages that have that element. I don't know if using this approach could replace some use of the color-scheme property within theme CSS.

But when CSS is disabled, maybe it makes more sense to let the user's prefers-color-scheme dictate the mode; that's what happens today. In that case, I'd either hide the solar eclipse toggle entirely or create a new disabled state, not HTML's disabled but changed to show something like "⊘ theming disabled" and for clicking to do nothing, visually and non-visually.

Start by locating the solar eclipse toggle and the pages containing a element. The issue presents alternative behaviors for CSS-disabled pages, so first clarify which behavior is wanted; done should include a defined toggle state and interaction that remains correct when CSS is disabled.