It seems the 'EXTJS 5.x inprogress' thread has been shut down, ending with a fairly close-minded "if you don't like it fix it yourself" type message (not a literal quote).
I don't know if that poster is an official representative of Sencha (I hope not), but it's an interesting coincidence that the thread is now closed to comments.
This kind of attitude is appalling. "Fix it yourself" is fine for open source software, but many of us PAY to use Ext.
I personally have discovered several regression bugs in Ext 4.2.x that are not related to my misuse of the code. They are bugs in the framework.
As I commented on the thread, waiting months between bugfix releases is harming the product, and is (I believe) a consequence of focusing too strongly on headline releases instead of getting the basics right.