Comments on: CSS hacks for IE-only style rules

By: Isofarro

Isofarro — Sun, 07 Mar 2010 20:43:14 +0000

Andrew, your approach would result in an extra HTTP request for IE-browsers, pulling in two external stylesheets. That adds to the perceived page-load times, plus a needless extra request on your webservers. For what? For the sake of having one CSS file pass a validation test, while another one still fails?

Sure, you can refactor the conditional comments approach so that there are two complete stylesheets, one with and one without the IE stylesheet hacks. That only then affects the success rate of caching a stylesheet. (That too can be refactored into one single stylesheet that also contains the IE stylesheet hacks – which is back to where we started)

In the long run, it would be better to have an invalid stylesheet that’s invalid in known, documented and accepted ways. Validation is a nice milestone in the destination for delivering a high quality site. It does need to be weighed with other factors, and determine the most effective compromise.

By: Steve Webster

Steve Webster — Mon, 09 Feb 2009 23:39:36 +0000

I’m pretty certain that after much spec searching, the conclusion we came to at work was that while _{property} and *{property} are not valid property names, the error handling part of the CSS specification means that standards-compliant browsers will ignore these properties.

In my opinion use of the star and underscore hacks is relatively safe, and there’s are performance and maintenance benefits to keeping all related styles together rather than separating IE stuff out into a conditionally-linked stylesheet.

By: Andrew Smith

Andrew Smith — Fri, 05 Dec 2008 12:50:42 +0000

Folks, it’s worth remembering that if “star” hacks (or any other hacks) are put inside an IE-only stylesheet, and referenced via conditional comments in the mark-up, the issue of compliancy does not apply. They are effectively off the radar.

And remember too that the “star” selector actually validates correctly against the w3c css 2.1 standard.

By: Mark Norman Francis

Mark Norman Francis — Thu, 20 Nov 2008 15:03:33 +0000

David – in my opinion, the “practical” part of web standards compliance is knowing when and why to break rules to achieve web sites (the primary goal).

By: David Dorward

David Dorward — Thu, 20 Nov 2008 12:48:05 +0000

While there are times when deviating from standards is *practical*, it isn’t *compliant*, and the tag line isn’t “Practical advice for building partially web standards compliant websites”.

By: Isofarro

Isofarro — Wed, 19 Nov 2008 08:56:12 +0000

David, yes, the CSS is invalid, yet the practical benefits of this technique far outweights the costs of it. And while we are stuck with Internet Explorer 6 and 7, we are stuck in a world where CSS isn’t as well supported in browsers as we’d like or expect.

Hence the tag line of site begins with “Practical advice”, rather than “Specification perfect”, our sites live and die on the Web with the browsers that our visitors use. There are times when validation needs to be broken for practical, and even accessibility considerations.

By: David Dorward

David Dorward — Tue, 18 Nov 2008 19:47:34 +0000

Given that this site has the tag line “Practical advice for building web standards compliant websites”, this seems like a odd post to see here.

The moment you use either the underscore or star hack, you are producing invalid CSS and making the site non-compliant.