Slash in folder name

In admin panel, when I insert a slash ("") in folder name of a page and I save the page, I get an error (red box) related to a “rename” problem. Right!
However a folder is create that has the name of the string before the slash.
Maybe it shoud, like slug property, slugify folder name also.

sorry, slash ("/"), not backslash.

If I recall correctly, slashes are not allowed in folder-names on any OS.

As you can see in this screenshot (“Advanced” tab in Page Edit), I can insert slashes.