It was the latest stable release - it was a manual upgrade from < 12, when it was pre-webkit.

I upgraded to the newest opera, and pages stopped being able to load. I knocked out my user profile, both in AppData/Roaming and AppData/Local; reinstalled Opera and still the pages are stuck on the "about:blank" page. I cannot even load opera settings or tools.

I uninstalled Opera, deleted the AppData files, and then installed a standalone version of opera. The same issue occurred here.

I'm using Windows 8.1 if that matters to anyone, although I think what is happening is some dependency that opera needs for rendering is not working properly.

Anyone have any ideas?