The hashing has to happen serverside, which means the server will temporarily have the plaintext in memory. While there, you can mutate the string by adding/rem

The hashing has to happen serverside, which means the server will temporarily have the plaintext in memory. While there, you can mutate the string by adding/removing/chanigng characters, to get a bunch of strings that are similar. Then you compare all of those to the old hashes you have stored. It will catch people doing common stuff like incrementing a number at the end on every reset.