这是在 The Web Standards Project 上看到的。
The Second Acid Test 是一个测试浏览器针对HTML，CSS，PNG等的支持的网页。其测试内容有：
- Transparent PNGs — The eyes are encoded as transparent PNGs.
- The object element — The eyes of the face are attached to an object element. Being able to use object (which can have alternative content) is one of the oldest requests from web designers.
- Absolute, relative and fixed positioning — Being able to position elements accurately is important for advanced page layouts.
- Box model — The original Acid test focused on the CSS box model. Acid2 continues in this fine tradition by testing ‘height’, ‘width’, ‘max-width’, ‘min-width’, ‘max-height’ and ‘min-height’.
- CSS tables — There is nothing wrong with table layouts. It is a powerful layout model which makes sense on bigger screens. However, the table markup is troublesome as it ties the content to these screens. Therefore, being able to specify table layouts in CSS is important.
- Margins — CSS defines accurate algorithms for how margins around elements should be calculated.
- Generated content — The ability to add decorations and annotations to Web pages without modifying the markup has long been requested by authors.
- CSS parsing — Acid2 includes a number of illegal CSS statements that should be ignored by a compliant browser.
- Paint order — We test that overlapping content is painted in the right order. This is not a feature in itself, but a requirement for other features to work correctly.
- Line heights — The Acid2 test checks a few key parts of the CSS inline box model, upon which any standards-compliant Web page depends.
- Hovering effects — One of the elements in the face changes color when you hover over it. Which one?
另外 The Web Standards Project 建的的另一个网站 browsehappy.com 也是一个很好玩的网站。它是一个指点人们如何选择网页浏览器的网站。网站的头条是：Internet Explorer can make your computer unsafe，然后里面收集了选用除IE外的其它各种浏览器（Mozilla，Firefox，Opera，Safari）的人们的使用心得。值得一看。