Apple today seeded the third beta of an upcoming macOS Sequoia 15.6 update to developers for testing purposes, with the software coming a week after Apple released the second macOS Sequoia 15.6 beta.
Developers can opt-in to the macOS Sequoia beta through the Software Update section of the System Settings app. An Apple ID associated with an Apple Developer account is required to get the beta.
Read more at MacRumors.com