unknown: wanted:    foo-ext -> foo
unknown: strip_addr foo-ext -> foo
unknown: wanted:    foo-ext -> foo -ext
unknown: strip_addr foo-ext -> foo -ext
unknown: wanted:    foo-ext@bar -> foo@bar
unknown: strip_addr foo-ext@bar -> foo@bar
unknown: wanted:    foo-ext@bar -> foo@bar -ext
unknown: strip_addr foo-ext@bar -> foo@bar -ext
unknown: wanted:    foo+ext@bar -> foo@bar +ext
unknown: strip_addr foo+ext@bar -> foo@bar +ext
unknown: wanted:    foo bar+ext -> foo bar +ext
unknown: strip_addr foo bar+ext -> foo bar +ext