> It isn't fixed because the problem you're seeing is completely unrelated to everything else described in this thread.
Both of these were happening a lot when Mountain Lion was released with Safari 6. You can see my own posts to this thread all the way to page 2, and if still in doubt about the issue discussed in this thread, consult the original post.
> In my experience, the other problems discussed in this thread (disappearing and reappearing text while typing, situations where the right half of a paragraph of text fails to scroll, etc.) seem to occur only in Safari on recent MacBook Pro hardware, and only when the Intel GPU is enabled.
Which is why I mentioned a problem related exclusively to zooming on Safari earlier, it may explain why the text rendering issues are more common on Retina MacBook Pros. That said, parts of pages not being displayed by scrolling very quickly is not an uncommon occurrence here, and add-ons such as Awesome Screenshots have lost their ability to capture entire pages as a result, because they need to scroll very fast in order to achieve that. Finally, just because you see text rendering issues mostly while using integrated graphics, that doesn't mean the problem is in any way related to that hardware or its driver, as I explained previously when I mentioned the possibility of undefined behavior being invoked by WebKit.
> By contrast, I can see what you're describing in Chrome on my six-year-old iMac, which has never exhibited either of the other problems, in and doesn't even have an Intel GPU.
A WebKit browser displaying WebKit rendering issues... How unexpected...