Yes, my bad. The entire screencapture task is run inside an XPC, which is started from the main app.

Thank you for your response and opinion. "I presume you mean an XPC service." - obviously. "why use screencapture" - simplicity, really. why reinvent the wheel, when something adequate already exists? "not least because it exposes you to binary compatibility problems" - an issue with any sort of relying on other peoples' code, and a constant worry in software development : D . well, I'll see how the review turns out and then re-assess. Thanks again.

other than that, I take it you don't have any insights as to what's changing in the screencapture tool in macOS Sonoma 14.4?

(and that is with ScreenCaptureKit, not the screencapture CLI)

In the meantime, I've also heard about other Mac App Store apps not launching, so it's not only my apps that aren't launching. And one of my customers just reported logging in to the Mac App Store with a different account, re-purchasing the app, and that suddenly works without a hitch. That same customer had reported earlier not being able to re-download the app with their original account, with the Mac App Store reporting error 5105.

referenced forum post: https://forums.developer.apple.com/forums/thread/764435?answerId=806097022