Is the page still in trash? If you look in trash, is *anything* there?
Nope. It never shows up in trash.
I have exactly the same problem. It occurs with a few different pages, but as far as I can tell all pages at the root level with a number of child pages at more than one level.
Please disable *ALL* plugins and change the theme to twentysixteen. If the problem goes away, then turn things back on one at a time until you find the culprit.
Hmm, sounds a good idea, but easier said than done, as this doesn’t happen instantly, but rather I notice occasionally that it has happened, seemingly randomly, when I am doing other work on the site, so I can’t just leave the site without plugins and unthemed for a long stretch…
I’ll see what I can do though…
http://www.oakhamteam.uk is the site btw
Yes that’s it exactly. The pages get __trashed added when saving the menu, and they are all pages where I have altered the description, and which currently matches the slug. PP Collaborative Editing Pack seems to be the problem, as disabling it gets rid of the problem.
Any idea why PP Collaborative causes it? We’ve been using it for well over a year and it just started. We need the plugin to control permissions to our site.
Please contact the developers of that plugin at http://presspermit.com/forums/