Update: After a few hours of this rumor percolating the internet, Google shot down the rumor with the following statement:

Hi folks, you may remember me from the last three releases where it looked like Dark Mode was being added. Unfortunately, this bug was closed prematurely due to a miscommunication with the team that handles AOSP issues.

What we have added in a future Android release is a developer-facing setting (via Developer Options) to toggle the -night UI mode qualifier, which will make it easier for developers to create and test apps that implement night mode. This qualifier has been in the platform since Froyo (SDK 8) and globally modifiable via UiModeManager since Marshmallow (SDK 23); however, there was never an explicit toggle made available anywhere in Settings.

If it's any consolation, we will also not be adding Hot Dog Mode (where all UI elements are yellow and red).

Oh well, it was fun while it lasted. Again. The original story is below.

Over the past few months, there have been a handful of indicators suggesting that Android will soon offer native theming support. Android Oreo allows users to customize their phones with the Substratum Theme Engine with the use of a simple desktop app, the Pixel 2 introduced white and dark themes that change based on the wallpaper you have set, and now it looks like Android will soon get a native dark mode.

Last November, one user took to Google's official Issue Tracker asking for a "Dark Mode or Night Theme in Android 9.0." Google responded a day later saying that it'd shared this suggestion with its engineering team, but after that, things went dark.

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However, during the wee hours of the morning on February 23, 2018, Google updated the thread once more with the following response:

Our engineering team has added this feature. It will be available in a future Android release.

AKA, a dark/black theme is finally coming to Android 🙌

Google's comment doesn't offer any insight as to when this feature will be launched, meaning it could debut as soon as Android P or it may not. This seems like a fairly small addition considering that Pixel and Nexus devices already offer this with accompanying wallpapers, so we'll be sure to keep an eye out for this during Google I/O in May.

Android P wish list: What I want Google to add