On Ethereum, it is possible to check whether a given message was signed by the user (not just by his software) by displaying a MetaMask window that asks user’s permission to sign a message.
What about doing the same on Internet Computer? Apparently, it can be done by creating a special black-holed canister that will display a dialog to sign a message.
My main question is, whether somebody already created such a canister? Maybe the nns.ic0.app provides this functionality? If yes, how?
I am willing to create such a signing canister, if it has not already be done.