The mass upgrade to Big Sur, it seems, caused the Apple servers responsible for these checks to slow to a crawl.Īpple quickly fixed the slowdown, but concerns about paralyzed Macs were soon replaced by an even bigger worry-the vast amount of personal data Apple, and possibly others, can glean from Macs performing certificate checks each time a user opens an app that didn’t come from the App Store.įor people who understood what was happening behind the scenes, there was little reason to view the certificate checks as a privacy grab. The cause: online certificate checks Apple performs each time a user opens an app not downloaded from the App Store. Last Thursday afternoon, Mac users everywhere began complaining of a crippling slowdown when opening apps.