What is your experience with Ext JS for building web applications, and what improvements would you suggest?

What is Ext JS used for?

How do you use Sencha ExtJS?

Is ExtJS dead?

Who introduced first version of Ext JS?

What is Ext JS framework?

Why do you think I should do web applications with extjs? Especially for a page that needs to be refreshed, and everything with AJAX? In such applications, debug works with 'click'. It can take a lot. But ultimately you can't hit the bug fix or see it refresh in the browser. Why is this necessary?

Currently Sencha Themer is available for all customers and that is a good thing. But I as a dedicated "lone wolf" customer will never become an enterprise customer. In that case I never have the benefit of using enterprise products. I don't even care at the moment of testing them, for if I like... Read more

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I would like to learn more about how various EXT-JS Users do the Migration from previous version to newer version and what has been their experience.