According to what Apple shared with developersInformation, Apple is planning to implement a pasteboard (i.e.iPhone(internal clipboard) to prevent Mac applications from reading the pasteboard without the user being alerted. In macOS 16, Mac users receive an alert when a Mac app reads the pasteboard without direct user interaction. This change means apps won't be able to secretly view what you copy and paste.
Mac users won't see alerts when performing actions directly related to the pasteboard, such as copying and pasting text in apps that support the feature. If an app attempts to view pasteboard data when the user is not using the paste functionality, the user will be notified.
Apple says the Mac clipboard will work similarly to the iOS clipboard going forward. On iPhone and iPad, Apple blocks apps from snooping on clipboard data, a step it has taken since iOS 14 after security researchers discovered that dozens of popular iOS apps read the contents of the clipboard without user consent.
Apple solved this problem by adding a banner that notifies you when an iOS app accesses the clipboard. In iOS 15, Apple has further enhanced this feature, introducing a safe paste option that prevents developers from fully viewing the clipboard unless you copy content from an app and paste it into the app you are using.
With an upcoming update for Mac, Mac developers will be able to "check the data types on the pasteboard" without actually reading them, improving pasteboard privacy. Pasteboard data using the privacy-focused API does not display alerts to end users. The following is Apple’s notice to developers:
Prepare your app for an upcoming macOS feature that alerts users of the device when your app programmatically reads the universal pasteboard. The system displays an alert only if the pasteboard access was not caused by user input on a UI element that the system considers paste-related. This behavior is similar to the behavior of UIPasteboard in iOS.
New detection methods in NSPasteboard and NSPasteboardItem enable apps to inspect various data on the pasteboard without actually reading the data and displaying an alert. NSPasteboard also adds an accessBehavior attribute that determines whether it is always allowed, never allowed, or whether an alert is prompted to request permission. You can adopt these APIs before making changes and set user defaults to test the new behavior on Mac.
Apple software engineer Jeff Nadeau mentioned on Mastodon that Apple has encountered some Mac applications that continuously grab the pasteboard in the background, but at the same time, there are also some applications that need to operate the pasteboard, which is why Apple designed the new API.
In some cases, Mac apps also require user permission to access the pasteboard. Apple says developers can test the upcoming pasteboard feature with their apps before the feature is officially rolled out to users.