Apple has issued a security update for Safari, fixing two flaws specific to the browser and 13 flaws in the underlying WebKit platform.
The Safari 5.0.1 and Safari 4.1.1 updates address vulnerabilities that could lead to data loss or remote code execution.
Amazon, Twitter, Bing and The New York Times are among the companies and services already offering extensions for Safari 5.0.1.
"We are thrilled to see so many leading developers creating great extensions, and think our users are going to love being able to customise Safari," said Brian Croll, vice president of OS X product marketing at Apple.
The Safari update follows browser patches this week from Google and Mozilla.
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