An update triggered by two Opera users.
An anonymous user wanted a last 5 disabled extension popup section like the 'Recent' section. I kind of see the use as I sometimes forget what I disabled. The functionality has been added as the 'Recently Disabled' section. ('Recent' is renamed to 'New & Updated'.
Terdale reported the bug where the alternate toolbar icon doesn't show on browser start. This is an old problem which kind of got complicated when I had Pushbullet running Chrome in the background. Somehow onStartup event wasn't working right with background apps running. Should be fixed now, at least its working for me.