After releasing the third OS X 10.10.2 pre-release version, Apple seeded individual Safari betas for testing via its developer program. This time, Apple made beta versions for OS X Mavericks and OS X Mountain Lion available from the developer portal as well. The latest Safari beta versions include Safari 6.2.3, Safari 7.1.3 and Safari 8.0.3.

In the recent releases, Apple tells developers to focus on the following areas of its web browser: General website compatibility, Extension compatibility, Password AutoFill, HTML5 video playback on popular video sites, Using the Web Inspector to debug websites, Reading List read/unread state, Editing bookmarks in the Favorites Bar and Bookmarks Sidebar, Website notifications.

As usual, any registered Mac developer can download the newest beta for Safari through the Software Update option through the Mac App Store or directly from the Mac Developer Center.

Source: Apple (Mac Developer Center)