Hi I did write a previous post on Demo Menu Items that cannot be deleted. I created a fresh installation, deleted the demo items, added one menu item, but now randomly the categories and menu item disappear from the admin page, but can be viewed on the frontend. I have posted images below
https://ibb.co/cLKcDGj
https://ibb.co/2nw0VVB
https://ibb.co/Qkg89LT