Thanks for the first and this reply btw.
The links states the topic: "How do I make a transaction with my Crypto Wallet on Opera for computers?"It shows the how the wallet should work and "confirmation" is done by the smartphone (I think on some way you are kind of right, with mirroring as I don't think the transaction is processed on the computer at all). The problem than is still that web3 is blocked and absolutly no website you should be able to connect the wallet to can be connected. They only recognise the address but no further information (like balance) can be queryed. Whatever the problem exactly is... the Team should free up the way to use MetaMask again or fix the communication betwen smartphone/computer/website.
You can check it out yourself by e.g. using Uniswap or MyEtherWallet