Apple is planning to implement a change to pasteboard (aka your iPhone's internal clipboard) that will prevent Mac apps from being able to read the pasteboard without the user being alerted, according to information Apple has shared with developers.
In macOS 16, Mac users will get an alert when a Mac app reads the pasteboard without direct user interaction. This change means apps won't be able to surreptitiously view the things you've copied and pasted.
Mac users won't see an alert with a direct pasteboard-related action, like when copying and pasting text within an app that supports it. Users will be notified if an app tries to view pasteboard data when the paste feature hasn't been used.
Apple says that the Mac pasteboard will work similarly to the iOS pasteboard going forward. On the iPhone and iPad, Apple blocks apps from snooping on pasteboard data, and has done so since iOS 14 after security researchers found that dozens of popular iOS apps were reading the contents of the pasteboard without user consent.
Apple addressed the problem by adding a banner that notifies you when an iOS app accesses the clipboard. In iOS 15, Apple further enhanced the feature by introducing a secure paste option that prevents developers from seeing the clipboard entirely unless you copy something from one app and paste it into the app you're actively using.
With the upcoming Mac changes, Mac developers will be able to "examine the kinds of data" on the pasteboard without actually reading them, improving pasteboard privacy. Pasteboard data used with the privacy-focused API won't show the alert to end users. From Apple's notice to developers:
Prepare your app for an upcoming feature in macOS that alerts a person using a device when your app programmatically reads the general pasteboard. The system shows the alert only if the pasteboard access wasn't a result of someone's input on a UI element that the system considers paste-related. This behavior is similar to how UIPasteboard behaves in iOS.
New detect methods in NSPasteboard and NSPasteboardItem make it possible for an app to examine the kinds of data on the pasteboard without actually reading them and showing the alert. NSPasteboard also adds an accessBehavior property to determine if programmatic pasteboard access is always allowed, never allowed, or if it prompts an alert requesting permission. You can adopt these APIs ahead of the change, and set a user default to test the new behavior on your Mac.
Apple software engineer Jeff Nadeau mentioned on Mastodon that Apple has come across Mac apps that are continuously scraping the pasteboard in the background, but at the same time, there are apps that need pasteboard manipulation, which is why Apple has designed the new APIs.
Mac apps will also need to get user permission to access the pasteboard in some situations. Apple says that developers are able to test the upcoming pasteboard changes with their apps ahead of when the functionality rolls out to users.
