I've got a strange problem.
On a fresh install of V4.3.6 the Categories work well with a drop down box that is quick and easy to use.
Then at some point of setting up my site it changes, as per the images.
It seems to happen when Categories are added/changed, or the Manage Stores information is updated. I have been able to replicate the issue on a fresh install but can't pin down what causes it or how to fix it.
Updating Categories with the dropdown box is quick and elegant, it will save me a lot of time in future if I can get it back.
I have cleared cache, browser, different browsers, stand on one leg etc...
Any help appreciated.