Can't point-and-click single object in plot edit mode of Boxplot

Hi everyone,

When I enter the plot edit mode, supposedly I should be able to select a single object by clicking on it, however, all objects just turn "selected" when I click on one single object. In addition, there is no simultaneous pop-out menu in property editor window for me to modify the object property.

This condition happens when I use boxplot function (it works well at least when I use plot function, but I haven't checked all other plot functions).

I am using student version R2013a.

Thank you very much! Tun