I don't think Apple will pay any attention if we posted feedback. They do what they want and couldn’t care less for the inconveniences of the customers. Didn’t we give you the OS for free??? Besides Mavericks is so full of bugs, as no other OS by Apple to date. I have been participating in other discussions for all the many bugs. Apple has so much work to do, I doubt they know where to begin with. Add to this the old bugs that were never resolved since Lion, like the Finder crashing after multiple drags of attachments in mail for storage to a locally shared drive, or even to folders in the same drive. I don’t want to get started with irrelevant to the subject here issues, but believe me there are MANY bugs that need attention. Now to the current problem, after further testing I concluded that Safari 5.1.10 needs to be excluded from the list of problematic updates. With other words the bug is limited to Safari 6.1 and 7.0 It comes to my mind that they implemented the sandbox per tab, taking the idea from Chrome, so maybe there is a faulty checkup hogging the system. While on Fedex page, the process of the tab crashes and since the other tabs have independent proceses Safari keeps rolling as nothing would have happened and only Finder reports the crash.