Don't know if it will work but you can try using an extension to change Opera user agent into chrome's one.
Of course! I forgot to tell it works if you mask Opera's UA-String removing the last part "OPR..."
I successfully use the Hangouts addon (install <em>CRX Extension Source Viewer</em> first and use it do install the <em>Hangouts</em> extension from Google). You might have to ”<em>Allow</em>“ cookies from talkgadget.google.com as well as hangouts.google.com in Opera's privacy settings, in case you selected to generally deny third party cookies.
The new hangouts.google.com works for me pretty well, though, either.