Google releases Pixel Feature Drop with December 2021 security patch from the Pixel 3a to the Pixel 6 and Pixel 6 Pro

Apps

• Fix for issue causing Assistant to unintentionally start a phone call in certain conditions *[1].
• Fix for stuck or frozen app UI in certain conditions *[7].

Audio

• General fixes & improvements for audio playback issues in certain apps *[1].
• Fix for issue causing audio noise in videos captured while using certain phone cases *[1].
• Fix for issue causing microphone to cut out during calls in certain conditions *[1].
• Fix for issue causing occasional audio glitch when adjusting volume levels *[1].
• Fix for issue occasionally preventing audio playback from speaker in certain conditions *[1].
• Fix for issue preventing Now Playing to search for unrecognized music *[1].

Battery & Power

• Additional improvements for battery charging information shown in notification shade *[4].
• General improvements for battery & thermal performance in certain conditions *[7].
• General improvements for wireless charging in certain conditions *[5].
• Improvements for alignment detection on Pixel Stand in certain conditions *[5].
• Fix for issues occasionally causing incorrect Battery usage accounting to display in Settings *[7].

Biometrics

• General improvements for fingerprint sensor stability & performance *[1].
• Additional fixes for issues preventing enrollment of new fingerprints in certain conditions *[1].
• General improvements for face unlock stability & performance *[6].

Bluetooth

• General Bluetooth stability improvements for certain conditions *[3].
• Fix for distorted audio over Bluetooth in certain scenarios *[1].
• Fix for issue causing Bluetooth to turn on after disabling in certain conditions *[7].
• Fix for volume adjustment issues with certain Bluetooth audio devices *[7].

Camera

• General image quality improvements in camera preview/capture *[1].
• General improvements for camera stability & performance *[1].
• General improvements for auto-focus response in certain capture modes *[1].
• General improvements for color consistency in viewfinder preview *[1].
• Fix for issue causing blank viewfinder preview in certain conditions *[1].

Display & Graphics

• Enable ANGLE graphics support library for certain apps and games *[1].
• Add additional example images for display color options in Settings *[7].
• General improvements to keep the screen on after multiple manual wakes *[7].
• General improvements for Adaptive brightness response in certain conditions *[7].
• Fix for occasional screen flicker during brightness adjustment *[1].
• Fix for issue preventing Smooth Display to switch display refresh rate in certain conditions *[1].
• Fix for issue causing screen flicker after locking or unlocking device in certain conditions *[1].
• Fix for occasional white screen flash after display goes to sleep *[7].

Framework

• Fix for issue causing app icons to display as pending downloads after installation completes *[7].
• Fix for issue causing Play store app installation to pause indefinitely in certain conditions *[7].
• Fix for issue occasionally preventing Work Profile setup to complete in certain conditions *[7].
• Fix for issue preventing all settings or apps to be restored from backup during setup in certain conditions *[7].

Media

• Fix for issue causing system crash during media playback in certain conditions *[7].

Network & Telephony

• General improvements for network connection stability & performance *[7].
• Fix for crash in Settings when toggling Airplane mode on certain network configurations *[7].
• Fix for issue that disabled call features on certain devices or networks in certain conditions *[1].

Sensors

• General improvements for sensor stability & response in certain conditions *[2].
• General improvements for Quick Tap response & performance *[2].
• General improvements for Auto-rotate response in certain device orientations *[4].
• General improvements for Adaptive brightness response in certain conditions *[7].
• Fix for issue preventing lift to wake and double tap to wake in certain conditions *[1].
• Fix for issue preventing Always-on-display from turning on in certain conditions *[1].
• Fix for issue causing unexpected haptics or vibration in certain conditions *[1].

System

• Kernel update to 4.9.279 for Pixel 3a & Pixel 3a XL.
• Kernel update to 4.14.243 for Pixel 4, Pixel 4 XL & Pixel 4a.
• Kernel update to 4.19.202 for Pixel 4a (5G), Pixel 5 & Pixel 5a (5G). 
• General improvements for system stability & performance *[7]
• Fix for issue causing device to freeze after sleeping while charging in certain conditions *[1].
• Fix for issue occasionally preventing OTA updates to install *[7].

User Interface

• Add Material You dynamic theming support for the device boot animation *[7].
• Improvements for Internet tile in Quick Settings *[7].
• Improvements for Quick Settings layout in certain device orientations *[7].
• Fix for issue causing display to stay on during wireless charging *[5].
• Fix for issue causing Game Dashboard icon to display over lock screen *[7].
• Fix for issue causing incorrect colors or theme to display in Quick Settings in certain conditions *[7].
• Fix for issue causing lock screen icons to display in notification shade in certain conditions *[7].
• Fix for issue causing notification History & Clear all buttons to occasionally display incorrectly *[7].
• Fix for issue causing persistent app media controls in notification shade in certain conditions *[7].
• Fix for issue causing persistent call notification in certain conditions *[7].
• Fix for issue causing persistent Turn off work apps button in app drawer *[7].
• Fix for issue causing screen flicker after locking or unlocking device in certain conditions *[7].
• Fix for issue causing Settings to crash in Conversations menu in certain conditions *[7].
• Fix for issue causing undismissable Game Dashboard button during gameplay in certain conditions *[7].
• Fix for issue causing app drawer to scroll to the top after clearing search query *[7].
• Fix for issue causing certain home screen icons to appear misaligned in certain conditions *[7].
• Fix for issue enabling Quick Settings toggles to be tapped from home screen in certain conditions *[7].
• Fix for issue hiding date or time in Quick Settings in certain conditions *[7].
• Fix for issue occasionally causing blank background on home screen after setting wallpaper *[7].
• Fix for issue occasionally causing Quick Settings to pull down after unlocking device *[7].
• Fix for issue occasionally causing UI elements to display with transparent backgrounds *[7].
• Fix for issue occasionally displaying Work Profile badge icon on personal apps or contacts *[7].
• Fix for issue preventing conversation bubble to be dismissed in certain conditions *[7].
• Fix for issue preventing search results to display in Settings in certain conditions *[7].
• Fix for occasional screen flicker in notification shade when dragging from top of screen *[7].
• Fix for occasional flickering when quickly switching between apps in certain conditions *[7].

Wi-Fi