Update: with the implementation of our redesign, we no longer offer a light theme option.
The light/dark mode on the forum will now follow your operating system’s settings. In case you want to override it, use the sun/moon icon at the bottom of the sidebar on the left of your screen.
I updated this topic - with the redesign we deprecated the theme switcher on the forum, I’m not sure it’s coming back. The staging option is a temporary ‘hack’ - it will be synced with the live theme soon.