Feature request from ihor-sviziev, posted on GitHub Dec 07, 2013
For now we using ExtJS version 1.1 Beta 1 (https://github.com/magento/magento2/blob/master/pub/lib/extjs/ext-core.js). Why we use really old lib? For now latest ExtJS version - 4.2.1!
Comment from verklov, posted on GitHub Jan 22, 2014
@igor-svizev , thank you for reporting this issue! We are considering this issue, but not yet have a decision about it. Please observe the repository for updates.
Comment from tkacheva, posted on GitHub Jan 29, 2015
@ihor-sviziev We are working on consistent usage of JS libraries in Magento 2. Follow the updates. Thank you.
Comment from mcspronko, posted on GitHub Jan 29, 2015
MAGETWO-25946