Why IE8 isn't passing Acid2?

Although we said that IE8 Beta 1 passes the ACID2 test, some of you may be seeing results like the image above; we thought we should explain what’s going on. IE8 passes the official ACID2 test hosted on http://www.webstandards.org/files/acid2/test.html. (Note, this seems to be a popular destination at the moment. You may have trouble reaching […]

Although we said that IE8 Beta 1 passes the ACID2 test, some of you may be seeing results like the image above; we thought we should explain what’s going on. IE8 passes the official ACID2 test hosted on http://www.webstandards.org/files/acid2/test.html. (Note, this seems to be a popular destination at the moment. You may have trouble reaching the site.)There are also a number of copies of this test around the net. One popular copy that I’ve seen of late is http://acid2.acidtests.org/

IE8 fails the copies of ACID2 due to the cross domain security checks IE performs for ActiveX controls.  Since IE does not natively handle HTML content in the OBJECT tag, but rather uses IE’s rendering engine as an ActiveX to display this HTML content, the same cross domain security checks also apply.

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Internet Explorer 8, IE8, Acid2, Testing