If you own OnePlus 6, here is how to enable a dark theme in Android 10. In OnePlus 6, the dark theme option isn’t available in the Display settings menu. Instead, it is a part of Customization, form where you can change the UI of your OnePlus 6/6T to dark or vibrant tints. You can also choose different clock styles for Ambient display, and wallpapers from the Customization menu. Along with Android 10 features, OnePlus added a few new features to OnePlus 6/6T with OxygenOS 10 update. For example, the new full-screen gesture features a left/right inward swipe to go back, and the bottom left/right navigation bar for switching recent apps. Contextual display (part of Customization) is another feature that brings intelligent info based on specific times/locations/events on the lock screen. If you haven’t updated your OnePlus 6 to Android 10 yet, check for it by going to the System update menu. Check this post for more information, OxygenOS 10 download link, and installation instruction for your device.