Dark theme
Now you can manually set light or dark theme in Android Q Beta 3 using display settings or quick settings tiles.
Settings > Display > Theme > Light or Dark
Turn on light theme in Android 10 Q using quick settings tiles
Swipe down notification panel from top of the screen > Tap Pencil icon > Hold and drag the Dark theme and move it to first tiles > Tap Dark theme
New Gesture navigation for Android 10 Q Beta
You can see three options for Android Q gesture navigation settings. Choose Android 10 gesture navigation control system from fully screen gesture / 2 navigation button / 3 navigation button
Step 1: Swipe down notification panel from top of the screen and tap Settings gear icon.
Step 2: Tap System settings at the end of the page
Step 3: Tap Gestures
Step 4: Tap System navigation
Step 5: Choose from fully gestural navigation / 2-button navigation / 3-button navigation