If you’ve updated to macOS Catalina 10.15.2 and installed any notarized apps since, you might have noticed that something has gone missing. Do you remember that dialog shown by Gatekeeper when you first open a notarized app, telling you that “Apple checked it for malicious software and none was detected”? Well, that sentence has now vanished. Instead, that dialog now looks very similar to the pre-Catalina dialog for non-notarized apps.

The only significant difference is that the Gatekeeper icon isn’t here defaced by a yellow warning triangle.

If you then go and check that dialog against Apple’s support note explaining how Gatekeeper works in Catalina and earlier, you’ll see that this new dialog doesn’t appear to exist in Catalina. You could be forgiven for assuming that your system had been subverted by malware, or the app you were just trying to open wasn’t notarized at all.

Indeed, Apple’s words there indicate that without this statement about Apple’s check for malicious software, the dialog could itself be malicious: “An app that has been notarized by Apple indicates that Apple checked it for malicious software and none was detected”. Many users interpret this as meaning that those specific words are Gatekeeper’s recognition that the app you are trying to open has been notarized. Without those words, surely that app hasn’t been notarized?

Other Gatekeeper dialogs don’t appear to have changed, though. Trying to open a non-notarized app with its quarantine flag set still shows the normal refusal.

And trying to bypass that using the Finder’s Open command still shows the extended three-button variant.

Full marks to Apple to making an unannounced and undocumented change which the observant user will almost certainly misinterpret badly.

Of course, as this is the result of a third-party product they’re trying to open, they won’t contact Apple Support, but that for the app. I’ve a good mind to bill Apple for all the support that I’m providing to cover the fact that Apple makes arbitrary changes at its whim without informing developers or users, and leaves us all wondering what the hell is going on.

Postscript

On further checking, the Gatekeeper first run dialog has changed more than shown above. Although I don’t appear to have an image of it in the initial release of Catalina, here it is in Mojave 10.14.6 (fully patched):

Here it is in Catalina 10.15.1, which shows that Apple had already removed the statement about checking for malicious software before 10.15.2:

And here for the sake of comparison is 10.15.2:

Maybe Apple wants to distance itself from the reliability of its checks for malware now. If it is going to change such critical dialogs so capriciously, at least it could keep its documentation up to date so that users know what they are supposed to see.

Perhaps our biggest lesson should be that hardly anyone reads important security dialogs like these any more, perhaps because they’re bombarded by so many. Have security and privacy dialogs perhaps become so commonplace as to be worthless?

I am very grateful to @12nanometers, who first drew my attention to this change, when he was concerned that my notarized apps weren’t notarized after all.