The current dominance of Google Chrome and Apple's Safari browser is damaging the standards of the web, according to Daniel Glazman, the co-chairman of the W3C's CSS standards working group. Chrome and Safari share the WebKit engine, and together currently account for around a third of all browser use. Glazman says that web programmers often overlook other browsers when they use newer CSS features designed specifically for WebKit, creating styles with no alternatives for other browsers to fall back on.

Representatives from Internet Explorer, Opera, and Mozilla have indicated that they see little option outside of implementing the WebKit-specific labels themselves, otherwise the increasing prevalence of built-for-WebKit sites could leave them left behind. This is a repeat of the same issues developers faced when coding sites for early versions of Internet Explorer — with a lack of apparent standards, it is easiest to aim for the most popular target.

In a blog post, Glazman has appealed to web developers to stop designing primarily for WebKit, especially where other browser-specific flags exist (e.g. -moz-, ms-* and -o-) to do the same jobs. However, the fact that this problem exist could be seen as a wider issue with the time W3C takes to finalize standards, and reflects frustration within the web developer community at having to write websites with so many different targets.