, not outside any of them.
If you apply margin or padding to div#fixedcontent, Mozilla adds this to the 100% height and width which results in double scrollbars. Because of that I have nested a div#innerbox and apply the padding to that instead. This does not seem necessary for MSIE 6.The scrolling content must be absolutely positioned for Opera 7.The fixed content can obscure other content, and can itself easily become obscured in small browser windows.
'position:fixed' in IE
Since the project I was working on for Q42 together with Sjoerd had to wait a little we thought it would be a good idea to update the site of their WYSIWYGXML Editor, Xopus. There are still a few minor mistakes on the site (validating and all that), but those do not make the site inaccessible or so. We also could not use UTF-8 (learn about UTF-8, leer over UTF-8) because the current httpd.conf file did not allow specifying a .htaccess and modyfying the server configuration file was not considered to be a good idea (and nobody who was around was sure if we were just allowed to read it, or if we could overwrite as well) just before the weekend. I guess those things will be fixed eventually. (Obviously, the same is true for putting mod_negotation to work.)
Anyway, the cool thing of the original site was the fixed top and bottom. It was done with some scripting that did not work cross browser. In Mozilla you could not scroll and in Safari the content was not shown. Although Xopus is a product just for Internet Explorer thanks to not supporting of (for example) contentEditable="true" in others the website could at least be made accessible so people using other browser then Internet Explorer could check what the product is about.
However, emulating position:fixed was rather tricky. I first thought of using some fixed positioning technique I developed ages ago, but did not quite emulate the intented effect. (In Internet Explorer it looks like you are using frames, which is not what we wanted.) There are some examples on the internet but most made the fixed element "flicker". You can see that here. Of course, you want better; position:fixed in IE. Although there are workarounds for Internet Explorer 6.0 in standards mode, just use quirks. It is so much easier, especially if you have to cope with Internet Explorer 5.5 (and even 5.0) as well.
The difference between the two files is background:url(foo) fixed. Although the existence of the file foo is not really needed, make sure 'foo' is some zero byte file to prevent stupid 404 requests. You might think the reference to foo is not needed at all and you can just write background-attachment:fixed. Unfortunately, that is incorrect. Internet Explorer probably runs a bit different when this setting is set.
All other things are pretty clear, I hope. Have fun.