Anigozanthos

Of late there's been quite a bit of hot air vented in various forum threads and blog comments in relation to Opera's apparent lack of "website compatibility".

Opera have over the years bent over backwards to provide "website compatibility". For version 9 they added support for the DOM Style module (completing their DOM2 support - the only browser to do so), XSLT, XPath, designMode/contentEditable, NTLM, opacity. For version 8 they added things like xmlhttprequest, SVG, DOM3 Load and Save, and fixed long-standing bugs related to iframe zindex and plugin transparency. For version 7 they completely rewrote their rendering engine to support reflow - vital for modern scripted web pages.

IMO, Opera have added so much compatibility and support, that we're now reaching a point where more often than not, it's website bugs that are causing the problem, not Opera bugs or lack of features.

Things are not helped when other more widely used browsers make mistakes, and web sites blithely assume those mistakes are actually correct. Internet Explorer is the usual villain, but lately I've noticed Firefox doing this sort of thing more and more. While Internet Explorer's problem is mostly Microsoft implementing their own standards and pushing them out to web developers, Firefox's problem is more insidious. What they're doing is allowing what should be internal browser functionality to be exposed to the web development community at large.

They most certainly aren't promoting the use of such things, but the general push by the Mozilla community to promote Firefox as a "standards based browser" (which it is) lends credibility to any random thing web developers may find while poking about Firefox features.

An example of this is Ajax13. "Ajax" makes it sound like the site is just using the usual XMLHttpRequest and associated Javascript that any modern browser should be able to handle. The reality is that the applications provided are all XUL based - and therefore only able to work with Gecko-based browsers such as Firefox. The idea that they're "web applications" is laughable - they're about as much web applications as Microsoft Office is - downloadable off the web and usable only on their designated platform.

Then there's other things, such as XMLDocument (mentioned in one of Hallvord's blogs), getBoxObjectFor, Event.originalTarget/explicitOriginalTarget, and the fact that Firefox allows registration of "capturing" event listeners without a murmur, even though it doesn't support them. I understand the latest Gecko engine (not available until Firefox 3) now supports event capturing, but before that they should have either done nothing (not register the event handler at all) or thrown a JS exception. Something to let web developers know there was something wrong!

Supporting the use of proprietary features and treating requests for an unsupported feature as requests for a different feature are just wrong, and make a standard-based web unnecessarily difficult. Microsoft can be excused because they were developing their browser engine before there were any recognised standards. The Mozilla guys don't have that luxury.