less know new features in macOS 15

Here are some lesser-known new features in macOS 15, also known as macOS Sequoia, based on the content presented at WWDC:

Writing Tools: macOS Sequoia introduces advanced writing tools that help with spelling, grammar, structure, clarity, and tone. These tools are integrated system-wide and can be automatically utilized by your apps (What’s new in AppKit).
Genmoji and Image Playground: These features allow for the creation of engaging experiences within your apps. Genmoji offers new ways to communicate, while Image Playground provides tools for effortless image creation (Platforms State of the Union).
Easier Window Tiling and iPhone Mirroring: Productivity features have been enhanced with easier window tiling and the ability to mirror your iPhone screen on your Mac (Platforms State of the Union).
User Space File System Support: New APIs have been introduced, including support for user space file systems, which can be leveraged to create more powerful and flexible file management solutions (Platforms State of the Union).
SwiftUI Customizations: macOS Sequoia includes new options to customize window behavior and styling, such as control over the window's toolbar and background, and a new text renderer API for advanced visual effects and animations (Platforms State of the Union).
SF Symbols and Toolbar Refinements: There are updates to SF Symbols and refinements to toolbars, providing more options for customization and better integration with your app's UI (What’s new in AppKit).

These features highlight the continuous improvements and new capabilities in macOS Sequoia that can help developers create more powerful and engaging applications.