I used Opera mainly for the Unite feature now to be abandoned.
It is missing in v. 12. Some say its features will re-emerge in future extensions etc. Until then, Unite is still accessible in v. 11. Where do I get the v.11 deb?
As opera-unite is no longer supported, it is possible that the server that provides the file sharing etc will soon be unaccessible.
Even if that is the case the question should maybe not be closed at it has a general usefulness independently of the unite
issue.
(It seems that in Windows upgrading from v.11 to v.12 keeps the unite
. Not in Ubuntu, as far as I can tell.)