Sys.Extended.UI is null or not an object

have installed 1.9 and  open the product detail page  and the rating  area  can not  be aviliable .
Then the page shows the below error

Webpage error details
Message: 'Sys.Extended.UI' is null or not an object
Line: 631
Char: 5
Code: 0
URI: http://......../.../product.aspx?productid=1
i have search about this error in google and can not  solve it. Does anybody have any idea what is causing this ?

https://www.nopcommerce.com/boards/t/9389/errorsysextendeduihtmleditortoolbarbuttonmethodbutton-how-to-fix-this.aspx