Just dropping by to say that https://fiddle.sencha.com has been updated to 4.2.2. My experience with the upgrade was that I did a simple Cmd upgrade:
This was the same for other internal tools I have created.
sencha app upgrade /path/to/ext-188.8.131.524
Working with Ext JS for years and being part of Sencha for almost 3 years, my experience with user issues is that a majority of issues are usually wrong implementation, only a portion (maybe 25%) are framework issues. How you do things in jQuery (or others) do not translate well to Ext JS and people blame Ext JS for this.
For bugs, there will always be bugs. This isn't a cop out, it's a valid statement for all software. For any product when I come across a bug, I try to report it with all information I can. Exact version, browser, browser mode but most importantly I give a clear test case. This is an area where https://fiddle.sencha.com is strong at.