Some sort of user-profile level corruption is causing Safari 5.1.8 in Snow Leopard to display any web pages as just plain text, formatted mostly in a single column, with only small thumbnails of graphics or no graphics at all, while the same web pages on the same computer look perfectly fine in FireFox and Chrome.
The corruption is only in my friend's main administrator user profile. When I create a new user profile for testing purposes, Safari works fine and displays pages correctly.
I have tried resetting Safari, in all categories, flushing all the caches and rebuilding permissions.
I have also "blown out" and deleted the user account, saving the home folder, and created a new user account with the same name, migrating the old home folder back to the new user account. Nothing helps.
Any suggestions as to how I might find and repair the corruption in the user profile that seems to be causing this?