当你决定输入这个关键词进行搜索的时候, 我猜你和我碰到了同一个的麻烦.
When you type this keywords in google. I guess you are in trouble like me.

新版本有时候会占用大量的CPU, 导致温度升高, 风扇变快, 最高记录是: 70度 6000转.
The new version make high cpu time, high temp and fast fan. The top record is: 160F 6000rpm.

Safari 无法从高版本直接降回低版本, 也没有提供卸载工具.
You cannot install the old safari directly, and there is not uninstall tool.

系统是如何判断版本的? 答案是:
How the os detect my version? The answer is:

/System/Library/Frameworks/WebKit.framework/Resources/Info.plist

把文件中的 “5530” 改成 “5525”, 也就是 Safari 3.2.3
Replace “5530” to “5525” in that file.

同时, 你还需要将 Safari.app 从应该程序里移走. 还有 ~/Library/Safari/ 下面的偏好设置, 否则 Safari 无法启动.
You need move away Safari.app from /Application to other folder. Also old preferens ~/Library/Safari/. Safari cannot run with them.

好了, 现在你可以安装 Safari 3.2.3 了.
OK~ You can install safari 3.2.3 now.

重启后, 首先启动一次 Safari, 然后将偏好设置放回去. 那个 TopSites.plist 应该没什么用.
After rebot. Open safari first then close it, move back you preferens file. Maybe you can drop TopSites.plist.