README.md in argon2-1.1.4 vs README.md in argon2-1.1.5

@@ -3,11 +3,11 @@
 This Ruby Gem provides FFI bindings, and a simplified interface, to the Argon2 algorithm. [Argon2](https://github.com/P-H-C/phc-winner-argon2) is the official winner of the Password Hashing Competition, a several year project to identify a successor to bcrypt/PBKDF/scrypt methods of securely storing passwords. This is an independant project and not official from the PHC team.
 
 
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 ## Design
 
 This project has several key tenants to its design:
 
@@ -42,9 +42,10 @@
 ```ruby
 hasher = Argon2::Password.new
 hasher.create("password")
 ```
 
+If you follow this pattern, it is important to create a new `Argon2::Password` every time you generate a hash, in order to ensure a unique salt. See [issue 23](https://github.com/technion/ruby-argon2/issues/23) for more information.
 Alternatively, use this shotcut:
 
 ```ruby
 Argon2::Password.create("password")
     => "$argon2i$v=19$m=65536,t=2,p=1$61qkSyYNbUgf3kZH3GtHRw$4CQff9AZ0lWd7uF24RKMzqEiGpzhte1Hp8SO7X8bAew"