Apple、デベロッパー向けに、macOS 12.3 beta 3 (21E5212f)、iOS 15.4 beta 3 (19E5225g)、iPadOS 15.4 beta 3 (19E5225g)、watchOS 8.5 beta 3 (19T5228d)、tvOS 15.4 beta 3 (19L5425e) を配布開始
https://developer.apple.com/news/releases/