Unfortunately, I can't tell exactely what has been done on the website, as many people work on it. Also, I'm pretty sure that this has nothing to do with a human intervention.
Obviously, Menu Sync seems to be the problem. Maybe something in the database ...
So, I did all what you suggest + I have rebuilt manually the Category Menu in FR.
As it was generated with Menu Sync, I though it could be a good idea.
So, I'm now waiting to see if this could be the end of this nightmare 😉
Unfortunately, the menu disappeared again. I installed an activity log, to see if someone as doing something wrong on the website, but it gave no result.
What I discovered, when I wanted to put back the translated menu, it is that when it is showing totaly empty, and if you add only 1 item and save, the translated menu comes back with its 160 product categories.
So, this tell me that it is deleted, but in a way, it still exist.
Also, as nothing is done to provoque this problem, and that it happens randomly, it must be the system that make it, maybe when cache is cleared or whatever the system does... and I think this has something to do with the database, as it only happens with 1 translated menu, and we have 2 of them.
Would it be possible to transfer that problem on a higher support level, as I think we did all the tests we could do ?
The bug came back and we lost our Category again, so I can sent you new Duplicator files containing the bug. Can you send me a private reply to send you the files ?
We suspect this is an issue with Object caching. First, you can exclude the "count" group from persistence caching or contact SiteGround support and ask them to exclude these groups from object caching (Memcached)
'counts', 'plugins', 'themes'
If they can not exclude these groups then you can add the code below to the file functions.php in the theme/child theme folder.
Then install any activity log plugin and if the issue happens again, please let us know any clue from the activity that can cause this issue. In order to debug this problem we need to know any clue to replicate it.
Can you send me a private reply to send you the files ?
No, thanks. I got a backup file of your site when the menu items are gone from the earlier.
So, I did all you said, including installing Simple History plugin.
I also have put back the menu, by adding only 1 item, ans as before, all the 160 items came back !
