Dark Mode toggle doesn't work

[Villi]

At the top of the page, there's a dark mode toggle. However, clicking on it doesn't enable dark mode, it just reloads the page. There is a button next to it that pops up the Customizer; all the options in the popup work, except for the Dark Mode option at the top - clicking on it exhibits the same behavior, it just reloads the page without enabling dark mode.

I tried this in Firefox and in Edge to make sure it wasn't a browser-specific problem.

I do use the Dark Reader extension, but it seems to have some difficulty giving this this forum a decent dark theme no matter which mode I use.

[Tripredacus]

Confirmed the (moon) button does "something" but it doesn't change the theme on the forum.