The other day in XCode 10.0, an error appeared when I uploaded the application to https://itunesconnect.apple.com (TestFlight).
One of these days there was a question on that how to export an Ethereum account from Metamask to Ethereum Wallet. It turned out all very simply.
Host or domain name not found. Name service error for name=gmail.com type=MX: Host not found, try again.
Need to use the show_user_profile, edit_user_profile, personal_options_update, and edit_user_profile_update hooks
If you need to clean local blockchain Geth + Ethereum Wallet (example for macOS), execute next commands