The pre-release version of Safari includes many WebKit enhancements and, most importantly, the new Web Inspector.
The updated Web Inspector in my opinion has become more convenient and friendlier to the developer, you can verify this by looking at the screenshots.

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New sidebar with general links in the form of a tape tweets of those to whom you are subscribed, with links. Not cheated and familiar bookmarks with a list for reading.


Top Sites also updated and it looks like tiles (yes, everything is now flat). I didn’t use this feature before, but now when the unnecessary volume has been removed, it has already become usable (a la Chrome).

You can download the beta with a developer account (for Safari Developer it is free).