User blog comment:BertH/Technical Update: March 9, 2016/@comment-1251315-20160310165827/@comment--20160310230558

In regards to "editing X wiki" and importing to "Y wiki", I don't think you're suppose to transfer over edit counts cross wiki. Seems like you're wanting to duplicate your edit count for two wikis. When a wiki is closed, your edits there are still technically recorded in Special:Editcount. I'm not quite sure you can transfer edit count on one wiki, to another. Even by merge. Perhaps I read that wrong, but seems to me you're wanting to "move edits" to another wiki.

As far as the masthead and user activity, seems like a bug to me.