Apple today quietly released an updated version of macOS Mojave 10.14.5, which is designed for 15-inch MacBook Pro models that feature a T2 security chip, aka the 2018 and 2019 machines.
The new version of the software can be downloaded through the “Software Update” section of System Preferences on all compatible Macs.
According to Apple’s release notes, the new software addresses a “firmware issue” impacting Macs with a T2 chip. Apple provided no additional detail, so we don’t know what the specific firmware issue might be, but we may get more information when the security notes become available.
Read more at MacRumors.com