According to http://msdn.microsoft.com/en-us/library/cc288325(VS.85).aspx IE8 can be made to mimic earlier IE version with tags like



Is this reliable enough to be used for testing web sites with (instead of using real browsers)? I recall IE6 in quirks mode didn't always render the same as IE5.x.

It's not really surprising you haven't received any responses, since this is an unanswerable question. Only the Evil Prince of Darkness Himself could (in principle) give a proper answer, and actually it would be long, loud, but on careful inspection devoid of content.

Remember that Microsoft does not have specifications for _anything_, including the behaviour of IE7 (that's why when the EC orders them to provide a spec, they say, "OK, we'll look at the code, and see if we can come up with something"). So it's pretty unlikely that _anyone_ could write a browser to perform to the (nonexistent) "spec" of IE7, or that Microsoft could really write something to reproduce all the previous bugs accurately.

I don't expect definite answers, more a general impression/consensus from those using both IE8 and IE7. I recall we had similar discussions about IE6 quirks mode vs IE5.


Here are some official differences, actually: http://blogs.msdn.com/ie/archive/2009/03/1...ty-and-ie8.aspx --alas it seems you can't tell what IE7 doesn't support by testing with IE8 in Compatibility Mode.


Yes it would be hard/impossible to reproduce the more obscure bugs, unless you simply put multiple rendering engines in the same browser (I recall Netscape 8? used both Trident and Gecko). But the well-defined incorrect behaviors should be documented in the IE changelogs, and therefore be easy to recreate.