prevent other people view saved password in Safara
I am using auto fill web forms of safari to store my user and password of some website. It is quite comfortable but there is only one disavantage and it is that I can view the passwords for some user without using master password. 

In firefox, we do have a master password so that it will restrict other people to view your saved password. 

How can i do that in Safari....

Please help if you know. Thanks
prevent other people view saved password in Safara
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I am using auto fill web forms of safari to store my user and password of some website. It is quite comfortable but there is only one disavantage and it is that I can view the passwords for some user without using master password. 

In firefox, we do have a master password so that it will restrict other people to view your saved password. 

How can i do that in Safari....

Please help if you know. Thanks