macOS 10.14.4 release notes:
The macOS Mojave 10.14.4 update adds support for Apple News+, includes bug fixes and improvements, improves the stability and reliability of your Mac, and is recommended for all users.
Apple News+
New subscription service that extends the Apple News experience with hundreds of magazines and top newspapers
Automatic downloads make it easy to read magazine issues offline
Apple News is now available in Canada, with a free experience that includes handpicked Top Stories, a personalized Today feed, and support for both English and French
Apple News+ is available in the U.S. and in Canada, with dozens of additional Canadian magazines
Safari
Adds Dark Mode support for websites that support custom color schemes
Streamlines website login when filling credentials with Password AutoFill
Allows push notification prompts only after interacting with a website
Adds a warning when an insecure webpage is loaded
Removes support for the expired Do Not Track standard to prevent potential use as a fingerprinting variable; Intelligent Tracking Prevention now protects against cross-site tracking by default
iTunes
Shows more editorial highlights on a single page in the Browse tab, making it easier to discover new music, playlists, and more in Apple Music
AirPods
Adds support for new AirPods (2nd generation)
More
Supports Air Quality Index in Maps for US, UK and India
Improves the quality of audio recordings in Messages
Supports real-time text (RTT) for phone calls made through a nearby iPhone on Mac
Provides enhanced support for external GPUs in Activity Monitor
Fixes an App Store issue that may have prevented adoption of the latest versions of Pages, Keynote, Numbers, iMovie, and GarageBand
Improves the reliability of USB audio devices when used with MacBook Air, MacBook Pro and Mac mini models introduced in 2018
Corrects the default screen brightness for MacBook Air (Fall 2018)
Fixes a graphics compatibility issue that may occur on some external displays connected to Mac mini (2018)
Resolves Wi-Fi connection issues that may occur after upgrading to macOS Mojave
Fixes an issue where re-adding an Exchange account may cause it to disappear from Internet Accounts
Fixes an issue where AOL user passwords may be frequently requested in Mail.
Source: 9to5mac