Link to switch themes (light/dark) without having to go in to user settings

Is there a link I can include in my header which would switch the users theme (from light to dark and vice versa) without having to click the top right icon, hit the cog, go and select the theme?

I find myself doing this each day and night. If not maybe a good feature request that (I can only assume) would be easy-ish to implement?

Apologies if asked before.

You may want to look at this theme component.

You can actually try it here on Meta. It allows you to switch to any user selectable from the hamburger menu: