"File not found" and "idleassetsd" continue data downloading at every boot/wake from standby

After upgrading my Macbook Pro to Sonoma, after every boot and every

wake-up from standby or basically unlock, a popup from Finder appear

with the "Cannot find the file" message and just an ok button to close.

Furthermore, idleassetsd is always downloading something at full speed of my network.

I guess this was because of the new motion-screensaver and it keep

downloading files but even after changed wallpaper and screensaver, at

least the Finder popup keeps appearing.