This question has been asked on the developers Forum but got closed down with no answer. Not sure why. We have also contacted them directly but the response was to : ask some one else.
We update our modules etc regularly, but the menu on the website had not changed for a while. Now when changing the menu order in the normal Joomla menu interface, then menu items in the mega menu drop down get duplicated. Restoring them to the original order removes the issue (!)
This must have come in somewhere between versions 2.6.2 through 2.6.5. I am using Joomla 3.7.2.
I have tried a bit of debugging in the plugin, and the json on the DB that it uses, but I can't figure out at which point the menu gets duplicated.
Question : has anyone else came across this issue ? does it some familiar.
Very happy if it's something I've overlooked or that I've done, rather than a bug.