sonoma 14.4.1 photos screensaver not working after upgrade

MacOS Sonoma 14 comes with new screensavers, so you may need to set your screensaver up again. This can happen when features are redesigned, like when the dock printing feature changed from an individual printer to "Print Center" in MacOS Ventura 13, causing the icon to crash and appear as a question mark. If this is your first time on MacOS Sonoma 14, this may be why. If you were already on a previous version of Sonoma, this may be a bug. Expect Apple to fix this in an upcoming update.

Also, keeping your screensaver on an external drive may not be a good idea, as bandwidth can be limited compared to your integrated disks. Local disks these days come with lots of storage - you should consider storing this on your local disk. If it's too large for your drive, you should reconsider having that much media on your screensaver. Screensavers loop, and most of the time, you're not going to be looking at it - your screen shouldn't stay on for more than 15 min when not in use.

I had to open photos up to reestablish the folder connection and the screen saver worked again. No changes to any settings.

If you want to use a single photo album, you should have an option to do so. If not, just drag your media from the album into a folder into the Finder, and you should be able to choose that folder, though this would take up space. If your photo album is not constantly updated, or if these images aren't taken on your iPhone, consider keeping these in Finder only instead of Photos.

Easiest way to do this is to export the pictures in the album to a folder and use that for a screensaver. Using the photo library for a screensaver hasn't been reliable for awhile. Though 14.4.1 broke screensaver for a folder of pictures as well...