I have the same problem, but i found a workaround. As mentioned if you unintentionally upgraded to 21.17.7 you cant connect to opera vpn. If you do this it works. Disable two modules 1) Ad blocker module, 2) Safe browsing module. When you diable both it works. I assume problem is safe browsing module because adblocker module just disables image loading bu safe borwsing completely eleminates web page. I cant found any options or adjustment inside the safe browsing that lets me browse in opera.