This report was prepared to accompany the transition of the April 2011 Proposed Recommendation of the Cascading Style Sheets Level 2 Revision 1 (CSS 2.1) specification to a W3C Recommendation.
Twenty four user agents, including HTML/CSS browsers and HTML to PDF converters, built from seven rendering implementations, were tested across eight operating systems.
The 23 March 2011 revision of the CSS 2.1 test suite was used. This test suite consists of 9418 tests, 227 of which test for optional behavior. These tests are available in several host language variants:
Some tests only apply to certain language variants; the results for each tested implementation are reported for each tested language variant. Also, not all tests are applicable to each implementation; for example, a browser which implements HTML but not XHTML is not tested for XHTML.
In summary, the results show that all 9191 tests for required behavior were passed by at least two of the tested implementations. In addition, 210 of the 227 tests for optional behavior were passed by at least two of the tested implementations.
Results were gathered from implementation reports submitted by user agent vendors as well as the general public via the CSS Working Group's Test Harness.