Well, I left a comment in the App store on Opera Mini review, linking this thread.
I gave 3 stars because I don't want to pull Opera down but I was hoping to raise some attention. It has not been approved or answered yet.
Does anyone have any idea what might cause this problem? Is there anything that requires some special setting on the user's side? I just faced this recently after I got my iPad. And I was fool enough to log out of Opera Mini on my iPhone, you know "just to test some things"... Now I'm completely out and lost. Such a dispair!
But you should be log in as applicant: https://praca.by/applicant/register/
HTTP_USER_AGENT: Mozilla/5.0 (iPhone; CPU iPhone OS 11_2_6 like Mac OS AppleWebKit/604.5.6 (KHTML, like Gecko) OPiOS/126.96.36.199049 Mobile/15D100 Safari/9537.53
the same as
Opera Mini 16 on iOS 11.2