Logging in, in Opera browser just freezes

...except try with a different browser.

I am not surprised by such answer. Instead of trying to diagnose the problem and solve it somehow, you just advice me to change a browser. Wow, that's really lazy.

Really? That's the first, and easiest, thing to do to see if the problem is with the specific browser or elsewhere! You stated

there's really nothing I can do about it.

I suggested the most elemental of diagnostic steps for you to try in response to your statement.

When you've finished moaning, please do let us know whether or not the problem persists with another browser.

Is it really moaning if I meet a cluster of issues everyday and support plays deaf-mute? Even reporting feature ideas for GC ends with expressive silence. I'm just tired of this kind of approach to customer.

But regarding the point,
Yes, on Firefox, logging in works fine, but it's not a solution for the problem. Some elements during logging in rediction clearly faults on Opera. It's not my job to diagnose the problem, I'm neither a QA, nor a service programmer.