Add card on Mac password update

mac-reset.md

+# Tips when resetting UL AD password with a Mac
+
+To reset your password when using a Mac, go to https://owa.uni.lu and change your password there.
+
+Before rebooting your Mac, you should change your keychain password to avoid any issues down the raod.
+You can use the following command to do that: `security set-keychain-password "/Users/YOURHOME/Library/Keychains/login.keychain-db"`
+
+If you use FileVault, after the first reboot, first enter your old password, then the new one.
+Normally, FileVault will sync and update with your new password after you reboot.
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