Q: How do I upgrade Safari?

Upgrade to the newest OS X v10.11 El Capitan.

See if your Mac meets the requirements here >  https://support.apple.com/en-us/HT201475

Then you could update to Safari 9.1 which is the latest version of Safari available.

If you decide to go ahead and upgrade to El Capitan, make sure to backup all your important data first.

If you're using a version older than 6.1.6, open the Mac App Store and check for updates. If you aren't, you need to upgrade the computer's OS or switch to a product such as Firefox.

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