In IE9, when you change pages with the same background image, it βblinksβ. In Firefox, page changes remain smooth, non-refreshing, and non-blinking background images.
When viewing http traffic, the header for the images is 304 - therefore, they should not be updated. Can I do something about this?
When you click this link with IE9, you can see the test page
This is the IE Developer F12 profile: 
CA Vuyk
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