Menu Actions Extremely Slow For Large Menus

[JoshRoy]

One of our sites has 350 items in one menu. In Chrome this causes the page to freeze for 30 seconds when the menu is first loaded in Appearance > Menus and again every time you try to move an item within the menu. It seems to be Chrome specific as it only takes Firefox a few seconds to perform the same actions.

I exported the site to a fresh copy of 3.9.2 without any plugins or themes and still had the same issue.

[johnbillion]

Thanks for the report Josh! This is a known issue. See #25698.