I found that the new Safari extension Newsguard sometimes prevents the horizontal menu from showing (which is stuck to top of page). Does not happen all the time.
What extension is that?
Thanks. And why would you say it’s NewsGuard instead of 1Password or Grammarly?
Process of elimination. The menu was not showing on my first page, so I viewed it with Google Chrome and it was working fine. I then turned all extensions off on Safari and it worked fine. Then I turned on each extension sequentially until only NewsGuard was on and the menu was not showing on the first page. All the other menus were fine - just the first one was missing. So I therefore concluded it was a problem with NewsGuard.