Safari 5 was released to the public in may. It has had mixed reception to be fair. On the other hand, many people have complained about performance and stability in Safari 5, compared to Safari 4.0.5. If, like others your having problems with Safari 5, and want to downgrade to Safari 4.0.5, use this guide to downgrade. This guide is for Mac OS X users only.
1: Archive and Install
The first way to get back to Safari 4.0.5 is to Archive and Install Mac OS X. Archiving and Installing does not remove any data (files, applications, settings etc.)
After Archiving and Installing, you do not do not install the Safari 5 update.
2: Using Pacifist
The next method you have is using some softwarecalled Pacifist. Download it then install it. Then you need to download Safari 4.0.5. Drag the Safari 4.0.5 installer onto the Pacifist icon and open it. Select Safari 4.0.5 in Pacifist, click Install and be sure to leave the “use administrator privileges” box checked.
When a dialog box that states “Application already exists,” pops up, put a check in “Don’t ask again for this installation,” and select “Replace.”
After , restart your Mac and you should be running on Safari 4.0.5
3: Use Time Machine
If you use Time Machine on your Mac, find Safari 4.0.5 in it, and roll back to that date. It is the easy option, but only if you use Time Machine.