IE9 in IE7 Compatibility Mode renders data URIs in css

Question

I'm testing a site in IE9 and using the compatibility mode to test in IE7 standards mode

few tweaks and everything is looking fine in IE7

However, I've noticed that all of the css is using data uris to images (you know the base64 fun of image inclusion). Which is fine and dandy.

However, IE7 doesn't support data URIs does it?! So why does IE9 in IE7 mode display them just fine?! If this is correct then IE9's compatibility mode is pretty useless for a complete IE7 test.

Am I correct?

Answer 1

Reason is that IE9 compatibility mode is not equal to IE7 (just compatible) and should not ever be used to test stuff for IE7. Do not depend on it.