Please ignore my last post. It was simply the page my friend sent me and it mirrored the issue, but was solely a problem with that website. I can't delete my post because it hasn't been approved and I can't find it to delete it before it shows up.

The update before the last one fixed this, but my browser updated again today and now I can't disable dark mode, nor does it fix when I restart. I even went to opera://flags/#enable-force-dark and it's disabled, but pages are coming up dark when they didn't when it was supposed to be fixed. Seemed the problem returned.