My eyes!!! Please Opera!!!
On my screen everything is dark, custom styles for all websites I use, all dark mode, window 10 dark mode, all my code editors are dark, Developer Tools in Opera are dark, only the address bar and active tab are light.
I picked a dark color for system so it is used by Opera 'Show system color on top bar', but it's not enough (also when Opera loses focus top bar become light back)....
A checkbox with 'Dark Mode' is required so much! Please!