Apple has released Catalina 10.15.4 Supplemental Update

Apple has released macOS 10.15.4 Supplemental Update, an out-of-cycle update which fixes:

  • problems taking part in FaceTime calls with devices running older versions of iOS or macOS;
  • problems with repeated password prompts for Office 365 accounts;
  • problems with the latest MacBook Air 2020, with hanging in Setup Assistant or when connecting or disconnecting 4K or 5K external displays
  • unresponsive USB-C ports.

This brings firmware updates for models with a T2 chip, taking them to version 1037.100.362.0.0, iBridge 17.16.14281.0.0,0. This means that those T2 models which haven’t had this Supplemental Update installed remain at the previous version, as do all T2 models running High Sierra or Mojave. I have now updated the database used by SilentKnight, and my listing here to show both old and new versions.

The download is 1.38 GB, or 1 GB using the standalone installer.

A standalone updater is also available from here.

Updated 0905 UTC 9 April 2020.