"macOS Big Sur 11.2.3 provides important security updates and is recommended for all users."

M1 Mini no HDMI video after macOS 11.2.3 Update (fixed)
M1 Mac Mini updated to 11.2.3 OK (from 11.2.1), but on the first (automatic) reboot for login after the update, there was no HDMI video output from the M1 Mini. Tried disconnect/reconnecting the HDMI cable, power cycling the Display (Samsung HM2493 1920x1200/60hz) - didn't help. Held the Mini's power button down (forcing a shutdown), then powered on and it booted up OK with HDMI working. (As noted earlier, this M1 mini has no 3rd party software/drivers installed and no migration from a previous Mac/OS. M1 Mac mini firmware is still v6723.81.1, no change since macOS 11.2 update.)

CVM Server Crashes still not fixed in Big Sur 11.2.3
Despite reporting it to Apple twice (with 11.2 and 11.2.1), macOS 11.2.3 does not fix the CVM Server crash with DVD Playback first seen with macOS 11.2. (Other M1 Mac users have also reported repeated CVM Server crashes since macOS 11.2 update. Often forcing a restart.)
 

• About the security content of Safari 14.0.3 (v.14610.4.3.1.7 & 15610.4.3.1.7)
  (There was a previous Safari 14.0.3 update on Feb. 1st.)
  - Available for: macOS Catalina and macOS Mojave.
  (After installing this update, the build number for Safari 14.0.3 is 14610.4.3.1.7 on macOS Mojave and 15610.4.3.1.7 on macOS Catalina.)
  
  
• iOS 14.4.1 release notes
  - This update provides important security updates and is recommended for all users.
• iPadOS 14.4.1 release notes
  - This update provides important security updates and is recommended for all users.
• About the security content of iOS 14.4.1 and iPadOS 14.4.1
  
  
• watchOS 7.3.2 release notes
  - This update provides important security updates and is recommended for all users.
• About the security content of watchOS 7.3.2

• Fixed dual graphics card layout issue.
• Updated Sparkle to version 1.26.0.
• Updated location and machine identification strings.
• Other minor fixes and enhancements.

• Apple to Build Europe Semiconductor Design Center in Munich (bloomberg)
  
  
• Tip for SOCD report detected: (AP watchdog expired) Crashes (apple forum)
  (This was posted before the Big Sur 11.2.3 update.)

  "(Apple Tier 2 Support Collected logs.) After 2 days they replied and asked me to see if it happens without drives connected. So far it doesn't happen with the WD drives disconnected. Been 7 days now without any issue and drives have been disconnected for these 7 days. Also doesn't happen with my sandisk usb flash drive connected."

  
  
• Apple TV+ announces programming partnership with Nobel laureate Malala Yousafzai (pr)
  
  
• Geekbench v5.4 released
  - See linked blog page for info on changes/fixes.
  
  
• Chrome 89.0.4389.90 Stable Channel Update (March 12th)
  - Includes 5 security fixes.

• (How to) Install and replace memory in your Mac Pro (2019)
  
  
• (How to) Install memory in an iMac (not removable in some models)
  
  
• If you get a personalization error when reinstalling macOS on a M1 chip Mac
  
  
• What's new in macOS Big Sur 11.2.3
  
  
• What's new for enterprise in macOS Big Sur
  
  
• Find out which macOS your Mac is using
  
  
• Apple web server notifications (security fixes)
  
  
• Availability of Apple Media Services
  (originally titled "What can I buy from the iTunes Store in my country?")
  
  
• How to use Voice Control on your Mac
  
  
• About iOS update and restore errors
  
  
• Use your iPad as a second display for your Mac with Sidecar
  
  
• If Personal Hotspot is not working on your iPhone or iPad (Wi-Fi + Cellular)
  
  
• Charge your AirPods with charging case and learn about battery life