Enable Dark Mode Theme on StackExchange

[elsiehupp]

Problem

I have a visual disability that leads me to use Dark Mode 24/7, and Dark Mode software support is a major focus area for me.

All modern web browsers support the prefers-color-scheme CSS media feature for automatically choosing between Light Mode and Dark Mode CSS styles.

StackExchange recently added a Dark Mode theme option to Stacks that allows individual sites to support the prefers-color-scheme CSS media feature.

Currently the Elementary OS StackExchange does not have this feature enabled.

Proposal

StackExchange recently added a Dark Mode theme option to Stacks that seemingly has to be enabled on the backend on a per-site basis. When the feature is enabled, the user can choose between "Light", "System" and "Dark" themes.

To be accessible as possible, the feature should default to "System" even for logged out users, but I don't know if the feature currently supports that.

Because respecting implicit user preferences is more accessible for site visitors with visual disabilities, you should implement this feature if at all possible.

Prior Art (Optional)

Stack Overflow is the only StackExchange site where I've come across this in the wild. If you log into Stack Overflow and go to Preferences, it should bring you to Settings > Site Settings > Preferences. The first panel in this section should be "Interface", and the first setting in that panel should be "Theme". This setting does not appear on the Elementary OS StackExchange site and presumably has to be enabled on the backend. If possible, you should make the setting default to "System" rather than "Light".

[JagveerGagaan]

can I start on this issue I will create a dark mode button with full functionality

[lewisgoddard]

I don't believe moderators have the ability to enable this, it is likely rolled out by StackExchange themselves.