The addon called PreformAVEnabler is stealing players logins and passwords. The server that it connects to is storing the accounts logins and passwords for a person to hack into their account and steal all of the gold including selling all items.
How do I know this? A friend in the game had recommended I use it to allow my characters in a raid to join AV without being in a group. He had his account stripped of his gear and lost all gold. One week after I installed the addon, my account had the same thing happen. I've never visited any websites other than blizzard.com, worldofwarcraft.com or battle.net. Also, I don't have anything running in my machine that would cause any form account theft. That is, I check my memory often with task manager and don't see anything that shouldn't be there.
The culprit is the PreformAVEnabler addon. Search for it on the web if you want to look at the addon code. But this is malicious and I am angry that addons are allowed to do this. There should be something to restrict an addon from stealing account logins and passwords.
If you don't believe me, keep using that addon and your account will eventually be stripped of all your gold.