For devices with OLED or AMOLED screens enabling dark mode can even provide power savings over traditional colour schemes.
Traditional LCD screens dont see the same power savings.
To be able to reach the parameters, tap the Opera icon in the bottom-right corner of the app.
To be able to reach the in-app tweaks, tap the Opera icon in the bottom-right corner.
Tap configs at the bottom of the popup menu, to pop fire up in-app configs.
Tap options at the bottom of the in-app options.
Tap Dark web pages to configure the dark web pages mode.
Select which setting you want to apply to all web pages.