If you want to build web sites that actually work, you have to take into account the wide variety of browsers that might visit, and take steps to make sure that everyone can use your site. The question is, what are you going to do when someone comes to your site in a browser that doesn’t actually work?
A lot of sites just fail, in that they are completely unusable. But a little forethought can keep the basics of your site usable for anyone. If your site is a full-on app and someone comes by in IE3, there’s nothing to do but tell them to come back with a real browser. But you can at least successfully do that! If you’re building a site for a restaurant, people really only want the address and hours, and you should be able to deliver that to any browser.
One of the earliest systematic attempts to handle this issue was Browser Grading: giving plausible browsers a grade for how good they were, and making sure they got appropriate content. For years, the king of browser grading was Yahoo, or actually, the Yahoo UI Library.
Yui evaluated browsers on 4 criteria:
Identified vs. Unknown There are over 10,000 browser brands, versions, and configurations and that number is growing. It is possible to group known browsers together.
Capable vs. Incapable No two browsers have an identical implementation. However, it is possible to group browsers according to their support for most web standards.
Modern vs. Antiquated As newer browser versions are released, the relevancy of earlier versions decreases.
Common vs. Rare There are thousands of browsers in use, but only a few dozen are widely used.
They then gave browsers one of 3 grades: A, C, or X.
A-Grade browsers were identified, capable, modern, and common. They were identified with a whitelist. They got full QA Testing
C-Grade browsers were identified, incapable, antiquated, and rare. They were identified with a blacklist. They got sparse QA Testing, but bugs were still addressed.
X-Grade browsers were all others. They were unidentified and QA did not test them.
A-Grade browsers got the full functionality of the site. X-grade browsers were assumed to be trying, and got the full functionality too.
C-Grade browsers…
C-grade is the base level of support, providing core content and functionality. It is sometimes called core support. Delivered via nothing more than semantic HTML, the content and experience is highly accessible, unenhanced by decoration or advanced functionality, and forward and backward compatible. Layers of style and behavior are omitted.
In February of 2007, YUI’s browser grading chart looked like this:
| Win 98 | Win 2000 | Win XP | Mac 10.3.x | Mac 10.4 | |
|---|---|---|---|---|---|
| IE 7.0 | A-grade | ||||
| IE 6.0 | A-grade | A-grade | A-grade | ||
| Firefox 2.0.* | A-grade | A-grade | A-grade | A-grade | A-grade |
| Firefox 1.5.* | A-grade | A-grade | A-grade | A-grade | A-grade |
| Opera 9.* | A-grade | A-grade | A-grade | A-grade | A-grade |
| Safari 2.0* | A-grade |
They had just dropped support for IE 5.5, Firefox 1.0, Netscape, and the Mozilla App Suite.
In 2010, they supported at A-grade IE 6, 7, 8 and 9, Safari 5, Firefox 3.6 and 4, Chrome (latest stable), and Android Webkit. C-grade browsers were listed as IE < 6, Safari < 3, Firefox < 3, Opera < 9.5, and Netscape < 8. They forecast that they would discontinue support for IE 6, dropping it to C-grade.
In 2011, they chickened out, and removed grades from their support page. You can find a list of dead links to their removed blog posts, if you want to grovel around in the internet archive and see what it used to look like. In fact, I wrote this post because all the source documents have been removed from the Internet.
Right as Yahoo was chickening out, jQuery Mobile was trying browser grading too. They had the guts to give out “F”s to Windows Mobile 6.1 and Blackberry 4.5 for a hot minute, if you want to grovel around in the Internet Archive.
They also gave “B”s:
B Medium Quality. Either a lower quality browser with high market share or a high quality browser with low market share.
They eventually settled on full support for A-grade browsers, support without AJAX page transitions for B-grade browsers, and plain but functional HTML for C-grade browsers.