Environment- test2, beta
1>Select Page Options -> Categories
2> Enter a category and click on the indicator-down.
3> In the resulting pop up enter a name in the "Sort this page as if it is called" input field for the category and hit enter to set the value. The popup closes.
4> Repeat step#2.Notice in the Category popup, the "Sort this page as if it is called" input field is blank. Screenshots attached.
Found in Chrome only.