I used before DevExpress and Kendo so allways I am using some windows to admin panel or properties of web portals which did by me.

last 1 week I am trying to test of ExtJs so if its ok I wanna write portal with ExtJs. when I am testing it Chrome and Mozilla ( on Samsung note ) I can not move windows and can not drag. but its ok on DevXpress and Kendo.
What is the different and are there any fix for it ?