I am dredging up this old thread because I found a better (
for me) solution some might want to try. It is call Dark Reader and is found
here for Chrome, Safari, Firefox and Edge. For Edge users, it can also be found at the Microsoft store
here.
I liked "Dark Mode" - when it worked properly. But I kept having problems with some sites, not just with consistencies displaying some pages in dark, but it interfered with some BBCode functions, like inserting links. So far, Dark Reader has not given me any problems.
There are some reports of Dark Reader not working properly on sites with their own dark mode themes enabled, but I have not encountered any myself - but I have not tried to break it either.