Desktop files appear and disappear randomly on MacOS Sonoma

I'm on Sonoma 14.6.1

Last week my desktop files all disappeared. If I opened the Desktop folder in Finder, there was nothing visible in it.

I've been to busy to debug the problem but yesterday the files suddenly came back. Yay! Then while I was using my MacBook Pro this morning, they disappeared again.

I searched here and found this discussion: Desktop files and folders hidden for seem… - Apple Community

Based on the discussion I tried pressing command-shift-period. The files appeared in both the Finder's Desktop folder and and on the Desktop, but grayed-out to signal that they are hidden files.

This has happened periodically to me over the last 3 years I have had the MacBook. I haver usually remediated by restoring from backup. However, this time I see the problem isn't that the files have disappeared but rather that they ALL got tagged as hidden in MacOS at once.

In fact, when they are hidden and I add a file to the Desktop, it appears and then almost instantly disappears - it's attribute is set to hidden.

This is beyond irritating!

Noting answers I have gotten before, iCloud Drive is on, but desktop and Documents folder are set not to sync. I only use it for app syncing. Instead I use Dropbox for backup. Because the problem appears and disappears without adjusting any Dropbox settings, I ruled out Dropbox as the cause of the problem.

[Re-Titled by Moderator]