Duplicating a UMAP causes heavy errors

For Leveldesign reasons i need an exact Copy of one of my Umaps.

First there is no Option for that in the Editor…
Done it in the explorer Manually.

When i now open up the Editor i have two maps with the same name…
Weird: They both are the same, if i change the first one the seconds gets changed too…
Also: The editor recongizes the umaps somewhere… so the duplicate is UNREMOVEABLE.

This is a serious Flowbreaking bug with also causes crashes and memory leaks.

What to do?

Works now pretty fine to me! Update 4.8.3 solved it.