By not using special chars in the first place, you can be sure you will not be able to run into any (unintentional) bugs later. And not using special chars is

By not using special chars in the first place, you can be sure you will not be able to run into any (unintentional) bugs later. And not using special chars is cheap, as by requiring a min-length of 13 instead of 12, you can get an even greater level of security.