Here is a (redacted) screenshot of me being prompted for a password (in xfce4-terminal):
Really! A password is being awaited - but somehow the prompt has got obfuscated by the curl stuff. If I press return, I get told the password is wrong and then prompted again (and if I supply the correct password - at this point or, by mystical intuition, earlier - all is dandy.) Can the command be modified so as to solve the problem.
EDIT: the curl command is recommended here, and it is my preferred way - apart from the problem - to install. And I don't fancy doing
su beforehand, and indeed I think there might be another post about a problem with doing that.