Hi,
A user logs in to the file vault, and DisableFDEAutoLogin is false. The file vault login succeeds, but the login to the selected user fails. The user gets the login screen again. If the user puts an invalid password to try and login again, the loginwindow:FDESupport plugin will change the user's password to the invalid one.
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Quinn “The Eskimo!” @ Developer Technical Support @ Apple
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