> At the time of their release, Opera was the most standards-compliant browser. That definitely does not correspond to my recollections. It was only in Opera 7

> At the time of their release, Opera was the most standards-compliant browser. That definitely does not correspond to my recollections. It was only in Opera 7 (2003) with the new Presto layouting engine that drastically improved standards compliance. > Beyond Opera, I'm not sure where Firebird, KHTML, etc. stood relative to IE4 specifically There wasn't any Firebird (neither Phoenix) at the time of IE6 release so how can you discuss this in relation to IE4 is beyond me. Mozilla Suite was still in 0.x beta and a year away from official release when IE6 was released. "The real work on KHTML actually started between May and October 1999" (wiki citation) so I don't think they had a big impact on the discussed time period. > but IE5.5/6.0 were well behind most contemporary browsers So let's get concrete, which browsers were better in 1999-2001? > It's worth remembering that Acid1 was released in 1998; IE6 was released in 2001. So this wasn't a time before web standards and cross-browser compat: they were very much a part of the discourse at the time. A discourse MS largely refused to participate in. Are you aware that IE6 is Acid1 compliant? IIRC the first one as the GA released browser (discounting Netscape 6/Mozilla 0.X betas). > Opera, KHTML, Firefox and Webkit all passed Acid2 long before IE (IE8 was the first version). Which is a direct consequence of the fact that Microsoft after IE6 release dissolved the IE development team. IE8 was the first substantial update of IE in 8 years. (IE7 was a minor update)