I have one Macs and two iOS devices running the App Store version of Enpass, and I set them synced via iCloud. Since yesterday I was trying to setup Enpass on a new Mac, but iCloud responded “Authentication Error: the action could not be completed. Please close the window and try again.” every time, when I choose Restore from iCloud in Enpass and pass the two-steps authentication in web browser.
I have no problem log in to iCloud.com in web browser on that machine, including signing on and two steps authentication. Just couldn’t authenticate Enpass.
macOS 10.14.6 & Safari 12.1.2.