Mega Menu issues - duplication of menu

[g-t-h-10BA]

I was making some changes to our mega menu (in a Team Site not associated with Office 365) and somehow have managed to duplicate the entire menu, which becomes visible only when hovering over one of the options. I can see no way to roll back to an earlier version of the menu to try and correct the fault and when I edit the mega menu options there's no duplication to be seen... Can anyone suggest any fixes?

[#2]

@g-t-h-10BA I have also experienced that Mega Menu behaves a little strange sometimes. I suspect it has something to do with the cache in my browser. The times I have had this problem I just clear the cache in my browser and restart it. When I've done that, it has worked as it should. You can try it and see if it helps you too.

[#3]

Thanks Magnus. Unfortunately it's not just my machine - everyone can see the duplication. Something has occurred within SharePoint...