Finder Favorites Disappear on iMac running macOS Ventura

My Finder Favourites have a a habit of disappearing. I have to go back to Finder/Settings Sidebar and click on Downloads/Documents/Desktop, also a folder have had dragged over to favourites. This happened often in Monterey and not very often in Ventura until recently where it is now very often.

I have not installed any new software of any type for months. Running the most recent version of the OS.

[Re-Titled by Moderator]