Same encryption salt used when encrypting all properties at once on key change

[ghost]

Whenever a key is changed, all of the properties that use that key are re-encrypted at once using the updated key. However, the same salt is used for all properties. This should be changed so that a different random salt is used to re-encrypt each property value.

@psmith

[psmith]

I'm having fun replicating this consistently. I managed to do it once, but can't do it again. I'll look into it more.