When Android 10 was officially introduced, fans of the dark mode were a little muted to see that several of the white apps had not yet been updated. The Google app, Play Store, Maps and Gmail were the biggest holdouts, but now it's finally dimming.
Signs of Gmail's dark mode pop up left and right – in settings, widget, and splashscreen – then our first real look at the entire app in the dark came from the official site of Android 1
Left : Gmail in the dark. Right : Customize a theme.
If invisible forces are to your advantage, you should see a themed menu in options settings to force Gmail to always be light, dark, or follow the standard system. If you have not been blessed by the gods of Google, you can be patient or manually activate it. The Reddit user u / careslol found a way, but it requires a root:
Go to data data com.google.android.gm shared_prefs FlagPrefs.xml
Search for "DarkThemeSupport" first flags) and change True. Save.
Force Gmail to close and reopen. Topic support should be available in the General Settings.
Anyway, it looks like you need to have v2019.08.18.267 in Gmail for this to work. You can get it from the Play Store or from the APK Mirror.