Håkon Wium Lie, author of the original CSS specification, has commented on this, and is demonstrating that the MSN is deliberately sending Opera a defective style sheet.
I wanted to find out if MSN had any "historical" reasons for treating Opera with a stylesheet that breaks so badly, so I downloaded the first Opera version, I’d say was widespread, Opera 3.62, and created a few screenshots. If you want to try yourself, Tommy A. Olsen keeps old versions of Opera archived. Most of these pre-adware versions of Opera offer a 30 day free trial.
Before reading on, you’d might like to download an archive of the screenshots for convenience.
When Opera 3.62 is served the page that all versions of Opera get, we see the same broken page that you would get by serving the same stylesheet to Opera 7 or MSIE. Opera 3.62 also breaks with the Netscape 7 stylesheet, moving text off to the left. Curiously enough, Mozilla does a better job with the Opera 7 stylesheet than either MSIE or any version of Opera. I’ll explain why later.
It should be duly noted that even in Opera 3.62 the IE6 stylesheet is the best suited one. Which proves: Opera’s CSS engine is mature enough. It was mature enough four years ago.
Modern browsers, as you may know, usually has a “quirks” mode, where they try to emulate the bugs and peculiarities of yesteryear’s browsers. This is triggered by which DOCTYPE declaration a document uses, or it’s triggered by the lack of such a declaration. Opera have information on how to trigger quirks mode in the different browsers.
MSN do not specify any doctype, and this will throw both Mozilla, Opera and MSIE into quirks mode. And this also explains why Mozilla treats the O7 stylesheet differently. While the quirks modes of both Opera and MSIE go to great lengths in emulating the bugs of Internet Explorer, Mozilla instead tries to emulate the bugs and peculiarities of Netscape 4.
If we try to view the msn.com page for either MSIE 6 or Netscape 6/7 with Netscape Navigator 4.8, the browser crashes. It works only when served the same stylesheet Opera is getting, and renders as intended.
Since the MSN front page always ends up being rendered in quirks mode, Mozilla ends up looking weird with the IE6 stylesheet.
So what should we make of this? Any version positively identifiable as Opera is being rendered with a stylesheet that largely is only compatible with Netscape 4, and browsers that clone Netscape 4’s rendering behavior. The only other browser with a noticeable marketshare that is able to mimic NS4 is Mozilla, and it’s offspring, like Phoenix and Netscape 6 or 7. None of these browsers is being served the NS4-compatible stylesheet. None. Instead they are being served a custom-crafted stylesheet for Mozilla browsers.
My personal conclusion on this is: MSN is deliberately sabotaging Opera. For what reason, I cannot tell. In one sense though, I think Opera should be flattered: Microsoft is obviously viewing the little Norwegian company as a large enough threat to use foul tactics to stop them.
My personal action is even simpler: MSN won’t be getting advertising revenue from me. I will not be using the MSN site. I’ll stick to portals and services that play fair.
Opera vs. MSN
Posted by Arve on 2003-02-06