Using Cmd 6.1.3, Ext 6.0.2
If I generate a new app, then run sencha app watch, the app works fine with Chrome. With Firefox (v47) it throws a 'not well-formed' error from classic.json and several 'unreachable code after return statement'(s) from ext-all-rtl. App shows okay, but does not respond correctly to mouse clicks. If I click on Users, Groups, or Settings the focus changes but nothing happens (if I then press space key, the choice works as expected). Are others experiencing this problem?