macOS Catalina 10.15.4 release: security improvements and moreIn late March 2020, Apple released another subversion of macOS Catalina. The new 10.15.4 iteration introduces a series of bug fixes and enhancements while additionally delivering security tweaks and feature updates. Compared to the previous build, this one appears to have more substantial changes under the hood and has a hue of finalization, which could mean that a fresh major macOS version is around the corner.
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macOS Catalina 10.15.4 release: security improvements and more